Información de la editorial
American Institute of Physics |
Documentos disponibles de esta editorial (326)
texto impreso
Hishiyama, N. ; Hoshino, M. ; Blanco Ramos, Francisco ; García, G. ; Tanaka, H. | American Institute of Physics | 2018-02-28As a sequel paper to our study of the elastic scattering for electron collisions with phosphorus trifluoride, PF? molecules, we report absolute inelastic differential and integral cross sections (DCS and ICS) of vibrational excitations for the c[...]texto impreso
Domínguez-Adame Acosta, Francisco ; Malyshev, Andrey ; Rodriguez, A. | American Institute of Physics | 2000-02-08We present results of numerical simulations of optical absorption line shape of Frenkel excitons in two-dimensional disordered lattices. Disorder is generated by Gaussian randomness in the molecular positions. The intersite interaction is consid[...]texto impreso
In this work, the ac admittance of a thick film nickel manganate spinel negative temperature coefficient thermistor ceramic system containing a glass phase is investigated. The dominating relaxation process is a grain boundary (GB) effect and ha[...]texto impreso
The dispersionless KP hierarchy is considered from the point of view of the twistor formalism. A set of explicit additional symmetries is characterized and its action on the solutions of the twistor equations is studied. A method for dealing wit[...]texto impreso
Balcells, Ll. ; Beltrán Finez, Juan Ignacio ; Martínez-Boubeta, C. ; Konstantinovi?, Z. ; Arbiol, J. ; Martínez, B. | American Institute of Physics | 2010-12-20In this work we report on the magnetic behavior of MgO thin films prepared by sputtering. A severe aging process of the ferromagnetic properties is detected in magnetic samples exposed to ambient atmosphere. However, ferromagnetism can be succes[...]texto impreso
AK Sco is a unique source: a 10-30 Myrs old pre-main sequence spectroscopic binary composed by two nearly equal F5 stars that at periastron are separated by barely eleven stellar radii so, the stellar magnetospheres fill the Roche lobe at perias[...]texto impreso
Ortega Villafuerte, Yanicet ; Fernández Sánchez, Paloma ; Piqueras de Noriega, Javier | American Institute of Physics | 2009-03-01Al doped ZnO arrays of nanoplates and of ordered nanoneedles have been grown by a thermal evaporation-deposition method. The nanoplates, which have mainly triangular shape. Interpenetrating triangles and crossing of the triangles with other plan[...]texto impreso
Through fractional calculus and following the method used by Dirac to obtain his well-known equation from the Klein-Gordon equation, we analyze a possible interpolation between the Dirac and the diffusion equations in one space dimension. We stu[...]texto impreso
Höft, Nicolas ; Horbach, Jürgen ; Martín Mayor, Víctor ; Seoane, Beatriz | American Institute of Physics | 2017-08-28We present a three-dimensional Ising model where lines of equal spins are frozen such that they form an ordered framework structure. The frame spins impose an external field on the rest of the spins (active spins). We demonstrate that this “poro[...]texto impreso
We analyze the band structure and interband optical transitions in a dangling backbone ladder DNA model. Using this model, semiconducting synthetic poly(G)- poly(C) DNA is studied by means of a tight-binding model traditionally used for transpor[...]texto impreso
Jaque, D. ; González Herrera, Elvira María ; Martín, J. I. ; Anguita,, J. V. ; Vicent López, José Luis | American Institute of Physics | 2002-10-07Arrays of submicrometric Ni lines have been fabricated in superconducting Nb films by electron beam lithography. In the mixed state, these arrays induce strong anisotropy in the dissipation behavior. The dissipation is reduced several orders of [...]texto impreso
Marín Palacios, Pilar ; Aragon, A.M ; Lieblich, M. ; Garcia Escorial, A. ; Crespo del Arco, Patricia ; Hernando Grande, Antonio | American Institute of Physics | 2012-07Magnetization curves of mixed Nb and FeSi based micrometric particles have been analyzed. The influence of the dispersion of Nb particles on the mixture remanence and coercivity has been studied above and below the Nb superconducting critical t[...]texto impreso
texto impreso
Brandao Fischer, Bruno ; Cubitt, Toby S. ; Lucia, Ángelo ; Michalakis, Spyridon ; Pérez García, David | American Institute of Physics | 2015We prove an area law with a logarithmic correction for the mutual information for fixed points of local dissipative quantum system satisfying a rapid mixing condition, under either of the following assumptions: the fixed point is pure or the sys[...]texto impreso
González Herrera, Elvira María ; Villegas, J. E. ; Varela del Arco, María ; Santamaría Sánchez-Barriga, Jacobo ; Prieto, P. ; Schuller, Ivan K. ; Vicent López, José Luis | American Institute of Physics | 2002-05-27Bi_2Sr_2CaCu_2O_8, RBa_2Cu_3O_7 (R=Y, Eu) thin films and RBa_2Cu_3O_7/PrBa_2Cu_3O_7 superlattices have been fabricated by sputtering technique. The anisotropic dissipation was measured close to the critical temperatures with high applied magneti[...]texto impreso
We show that vector theories on cosmological scales are excellent candidates for dark energy. We consider two different examples, both are theories with no dimensional parameters nor potential terms, with natural initial conditions in the early [...]texto impreso
Martínez, José I. ; Abad, Enrique ; Beltrán Finez, Juan Ignacio ; Flores, Fernando | American Institute of Physics | 2013-12-07The interface between the tetrathiafulvalene/tetracyanoquinodimethane (TTF-TCNQ) organic blend and the Au(111) metal surface is analyzed by Density Functional Theory calculations, including the effect of the charging energies on the molecule tra[...]texto impreso
Herrero Gómez, Carlos ; Marín Palacios, Pilar ; Hernando Grande, Antonio | American Institute of Physics | 2013-09-30In the present paper, we report a systematic study of the magnetoelastic resonance of amorphous magnetic microwires of composition Fe73Si11B13Nb3. The study was performed for samples annealed at different temperatures. It was observed that such [...]texto impreso
Mártil de la Plaza, Ignacio ; González Díaz, Germán ; Prado Millán, Álvaro del ; San Andres Serrano, Enrique | American Institute of Physics | 2003-12-15The composition, bonding configuration, hydrogen content, and paramagnetic defects of SiOxHy thin films were studied. Films were deposited by the electron cyclotron resonance plasma method at room temperature using SiH4 and O-2 as precursor gase[...]texto impreso
The electromagnetic self?interaction of a bound classical nonlinear Dirac field in a Coulomb potential is studied. It is shown that by a finite renormalization procedure the radiative corrections can be eliminated at order ?2, after which the en[...]texto impreso
Gómez Nicola, Ángel ; Cebollada, F. ; Palomares, F. J. ; Sánchez, N. ; González Herrera, Elvira María ; González, J. M. ; Vicent López, José Luis | American Institute of Physics | 2014-03-10In this work, we improve the ability to tailor the switching mechanism in nanomagnets by introducing an additional, highly controlled source of anisotropy: magnetocrystalline anisotropy. We analyze the vortex dynamics in single crystal Fe nanotr[...]texto impreso
Dobado González, Antonio ; Llanes Estrada, Felipe José ; Torres Rincón, Juan M. | American Institute of Physics | 2010We introduce the concept of viscosity (both shear and bulk) in the context of hadron physics. and in particular the meson gas, highlighting the current theoretical efforts to connect possible measurements of the viscosities to underlying physics[...]texto impreso
Ciliberti, S. ; Grigera, T.S. ; Martín Mayor, Víctor ; Parisi, G. ; Verrocchio, P. | American Institute of Physics | 2003-10-21A simple model of harmonic vibrations in topologically disordered systems, such as glasses and supercooled liquids, is studied analytically by extending Euclidean random matrix theory to include vector vibrations. Rather generally, it is found t[...]texto impreso
We discuss generalizations of the well known concept of canonical transformations fo symplectic structures to the case of hyperkahler structures. Different characterizations, which are equivalent in the symplectic case, give rise to non-equival[...]texto impreso
Gómez, P. ; Jiménez, J. ; Martín, P. ; Piqueras de Noriega, Javier ; Domínguez-Adame Acosta, Francisco | American Institute of Physics | 1993-11-15The effect of oxygen loss on the luminescence of YBa_2Cu_3O_(7-x) has been investigated by cathodoluminescence (CL) in the scanning electron microscope (SEM) and by Raman microprobe measurements. The results herein indicate that a CL band at 530[...]texto impreso
Cremades Rodríguez, Ana Isabel ; Santos, M. T. ; Remon, A. ; Garcia, J. A. ; Dieguez, E. ; Piqueras de Noriega, Javier | American Institute of Physics | 1996-05-01Cathodoluminescence and photoluminescence of Bi_(12)Si_(O)20 and Bi_(12)GeO_(20) samples are studied. Both kinds of samples show a dark orange central part or core. Emissions in the blue, green, and red spectral regions are observed. The 640 nm [...]texto impreso
Cathodoluminescence and photoluminescence in the core region of Bi_12GeO_20 and Bi_12SiO_20 crystals
Cremades Rodríguez, Ana Isabel ; Santos, M. T. ; Remon, A. ; Garcia, J. A. ; Dieguez, E. ; Piqueras de Noriega, Javier | American Institute of Physics | 1996-05-01Cathodoluminescence and photoluminescence of Bi_12SiO_20 and Bi_12GeO_20 samples are studied. Both kinds of samples show a dark orange central part or core. Emissions in the blue, green, and red spectral regions are observed. The 640 nm band is [...]texto impreso
Díaz-Guerra Viejo, Carlos ; Piqueras de Noriega, Javier ; Volciuc, O. ; Popa, V. ; Tiginyanu, I. M. | American Institute of Physics | 2006-07-15Cathodoluminescence (CL) microscopy and spectroscopy have been used to investigate the optical properties of GaN microstructures patterned by Ar+ ion irradiation and subsequent photoelectrochemical (PEC) etching. Monochromatic CL images and CL s[...]texto impreso
Maestre Varea, David ; Cremades Rodríguez, Ana Isabel ; Piqueras de Noriega, Javier | American Institute of Physics | 2004-03Cathodoluminescence (CL) in the scanning electron microscope (SEM) has been used to investigate the luminescence mechanisms in tin oxide. Sintered material prepared from high purity powder has been found to show a strong dependence of the CL emi[...]texto impreso
Díaz-Guerra Viejo, Carlos ; Piqueras de Noriega, Javier ; Golubev, VG. ; Kurdyukov, D.A. ; Pevtsov, A. B. | American Institute of Physics | 2001-10-01Synthetic opals infilled with silicon (opal-Si) and with Si and Pt (opal-Pt-Si) have been irradiated in a scanning electron microscope under high excitation conditions. Electron irradiation-induced changes in the morphology and luminescent defec[...]texto impreso
Wang, K. ; Martin, R. W. ; Nogales Díaz, Emilio ; Edwards, P. R. ; O’Donnell, K. P. ; Lorenz, K. ; Alves, E. ; Watson, I. M. | American Institute of Physics | 2006-09-25AlInN layers implanted with europium and erbium ions are systematically studied and compared with similarly implanted GaN. Cathodoluminescence from four series of annealed samples shows that the Eu/Er emissions from AlInN are considerably broade[...]texto impreso
Cremades Rodríguez, Ana Isabel ; Piqueras de Noriega, Javier ; Solís, J. | American Institute of Physics | 1996-05-15Planarization of large grain diamond films has been induced by 193 nm excimer laser irradiation. Secondary emission images and cathodoluminescence (CL) in the scanning electron microscope have been used to characterize-the irradiated area. Irrad[...]texto impreso
Cremades Rodríguez, Ana Isabel ; Piqueras de Noriega, Javier ; Xavier, C. ; Monteiro, T. ; Pereira, E. ; Meyer, B.K. ; Hofmann, D. M. ; Fischer, S. | American Institute of Physics | 1996-12-15GaN epitaxial layers have been investigated by cathodoluminescence (CL) in the scanning electron microscope (SEM). The most prominent feature of the spectra is a complex band at 2.2 eV, whose evolution with temperature and excitation density sug[...]texto impreso
Díaz-Guerra Viejo, Carlos ; Vincent, J. ; Piqueras de Noriega, Javier ; Bermudez, V. ; Dieguez, E. | American Institute of Physics | 2005-01-15The radiative recombination properties of Se-doped GaSb crystals grown by the Bridgman method have been investigated by cathodoluminescence (CL) microscopy and spectroscopy in the scanning electron microscope. A CL band centered at about 765 meV[...]texto impreso
A formalism is presented in order to impose causality conditions for finite?range interactions which do not require the existence of wave packets with a sharp front. The absence of bound states and particle production is assumed. Two different c[...]texto impreso
Domínguez-Adame Acosta, Francisco ; Piqueras de Noriega, Javier | American Institute of Physics | 1991-01-01Grain boundaries in GaP and InP have been studied by infrared cathodoluminescence (CL). In GaP the results indicate that there exists a depletion region beside grain boundaries where the concentration of P(Ga) antisite defects is lower than in t[...]texto impreso
Rezgui, B. Drid ; Gourbilleau, F. ; Maestre Varea, David ; Palais, O. ; Sibai, A. ; Lemiti, M. ; Bremond, G. | American Institute of Physics | 2012-07-15Experimental investigation of photoconductivity in Si-rich silicon oxide (SRSO)/SiO_2 multilayer (ML) structures prepared by magnetron reactive sputtering is reported. Photocurrent (PC) measurements show that the PC threshold increases with decr[...]texto impreso
We study the dependence of the ? ? scattering phase shifts on the light quark mass in both standard and unitarized SU(2) Chiral Perturbation Theory (ChPT) to one and two loops. We then use unitarized SU(3) ChPT to study the elastic f_0(600), k(8[...]texto impreso
Guzmán Navarro, G ; Herrera Zaldivar, M. ; Valenzuela Benavides, J. ; Maestre Varea, David | American Institute of Physics | 2011-07-01We report a cathodoluminescence (CL) study of ß-Ga_2O_3 nanowires grown by thermal evaporation of GaN on Si(100) and Au/Si(00) substrates. Condensation and subsequent oxidation of metallic Ga is suggested as the growth mechanism of ß-Ga_2O_3 nan[...]texto impreso
texto impreso
Bourhrous, Hassan ; Cruz Dombriz, Álvaro de la ; Dunsby, Peter | American Institute of Physics | 2012We present a description of CMB anisotropies generated by tensor perturbations in f(R) theories of gravity. The temperature power spectrum in the special case of f(R) = Rn is computed using a modified version of CAMB package.texto impreso
Marín Palacios, María Pilar ; Aragón, A. M ; Garcia Escoria, A. ; Lieblich, M. ; Crespo del Arco, Patricia ; Hernando Grande, Antonio | American Institute of Physics | 2013-01-28Fe_(73.5)Si_(13.5)B_9Nb_3Cu_1 powder particles have been obtained by gas atomization. Magnetization curves and coercivity were studied for particles ranging in size up to 1000?. The overall magnetic behavior of such material is consequence of c[...]texto impreso
Rosado Vélez, Jaime ; Blanco Ramos, Francisco ; Arqueros Martínez, Fernando | American Institute of Physics | 2011Experimental results of the absolute air-fluorescence yield are given very often in different units (photons/MeV or photons/m) and for different wavelength intervals. In this work we present a comparison of available results normalized to its va[...]texto impreso
González Díaz, Germán ; Artús, L. ; Blanco, N. ; Cuscó, R. ; Ibañez, J. ; Long, A.R. ; Rahman, M. | American Institute of Physics | 2000-12-01We have verified the accuracy of free-charge determinations from Raman scattering in doped semiconductors by comparing the results obtained from phonon-plasmon coupled-mode line-shape fits with the charge-density values extracted from the analys[...]texto impreso
Bedeaux, D. ; Ortiz de Zárate Leira, José María ; Pagonabarraga, I. ; Sengers, J. V. ; Kjelstrup, S. | American Institute of Physics | 2011-09-28In this paper, we consider a simple reaction-diffusion system, namely, a binary fluid mixture with an association-dissociation reaction between two species. We study fluctuations at hydrodynamic spatiotemporal scales when this mixture is driven [...]texto impreso
Ortiz de Zárate Leira, José María ; Sengers, Jan V. ; Bedeaux, Dick ; Kjelstrup, Signe | American Institute of Physics | 2007-07-21In this paper a simple reaction-diffusion system, namely a binary fluid mixture with an association-dissociation reaction between the two components, is considered. Fluctuations at hydrodynamic spatiotemporal scales when a temperature gradient i[...]texto impreso
A new causal boundary, which we will term the l-boundary, inspired by the geometry of the space of light rays and invariant by conformal diffeomorphisms for space-times of any dimension m ? 3, proposed by one of the authors [R. J. Low, The Space[...]texto impreso
Navascués Cobo, Miguel ; Pérez García, David ; Junge, Marius ; Palazuelos Cabezón, Carlos ; Scholz, V. B. ; R. F. Werner, R. F. | American Institute of Physics | 2011We show that Tsirelson's problem concerning the set of quantum correlations and Connes' embedding problem on finite approximations in von Neumann algebras (known to be equivalent to Kirchberg's QWEP conjecture) are essentially equivalent. Specif[...]texto impreso
Gómez Nicola, Ángel ; Gilbert, D. A. ; González Herrera, Elvira María ; Liu, Kai ; Vicent López, José Luis | American Institute of Physics | 2013-02-04Hybrid superconducting/magnetic nanostructures on Si substrates have been built with identical physical dimensions but different magnetic configurations. By constructing arrays based on Co-dots with in-plane, out-of-plane, and vortex state magne[...]texto impreso
Hoyo Muñoz, Jesús del ; Martínez Vázquez, Rebeca ; Sotillo Buzarra, Belén ; Teddy Fernández, Toney ; Siegel, Jan ; Fernández Sánchez, Paloma ; Osellame, Roberto ; Solís Céspedes, Francisco Javier | American Institute of Physics | 2014Local compositional changes induced by high repetition rate fs-laser irradiation can be used to produce high performance optical waveguides in phosphate-based glasses. The waveguide refractive index contrast is determined by the local concentrat[...]texto impreso
Sotillo Buzarra, Belén ; Escalante, G. ; Radoi, C. ; Muñoz San José, V. ; Piqueras de Noriega, Javier ; Fernández Sánchez, Paloma | American Institute of Physics | 2019-12-14The effect of plastic deformation on the optical and structural properties of ZnSe crystals has been investigated. The optical properties have been monitored by cathodoluminescence measurements as a function of the deformation degree. Remarkable[...]texto impreso
Abdelwahab, Mohamed ; Cruz Dombriz, Álvaro de la ; Dunsby, P.K.S. | American Institute of Physics | 2013We study for the first time a complete analysis of the imprint of tensor anisotropies on the Cosmic Microwave Background for a class of f(R) gravity theories within the CAMB-PPF framework. Herein we present the most relevant equations, both for [...]texto impreso
Llanes Estrada, Felipe José ; Cotanch, Steve ; General, Ignacio ; Wang, Ping | American Institute of Physics | 2008The Coulomb gauge model, involving an effective QCD Hamiltonian in the Coulomb gauge, is applied to scalar hadrons. Mass predictions are presented for both conventional q ¯ q meson and q ¯ qq ¯ q tetra-quark states. Mixing matrix elements betwee[...]texto impreso
Hoshino, M. ; Limao Vieira, P. ; Suga, A. ; Kato, H. ; Ferreira da Silva, F. ; Blanco Ramos, Francisco ; García, G. ; Tanaka, H. | American Institute of Physics | 2015-07-14Absolute differential cross sections (DCSs) for electron interaction with BF3 molecules have been measured in the impact energy range of 1.5-200 eV and recorded over a scattering angle range of 15 degrees-150 degrees. These angular distributions[...]texto impreso
Mártil de la Plaza, Ignacio ; González Díaz, Germán ; Sánchez Quesada, Francisco ; Santamaría Sánchez-Barriga, Jacobo ; Iborra, E. | American Institute of Physics | 1987-11-15Structural, compositional, optical, and electrical properties of CuInSe2thin filmsgrown by rf reactive sputtering from a Se excess target in Ar/H2 atmospheres are presented. The addition of H2 to the sputtering atmospheres allows the control of [...]texto impreso
If dark energy can be described as a perfect fluid, then, apart from its equation of state relating energy density and pressure, we should also especify the corresponding rest frame. Since dark energy is typically decoupled from the rest of comp[...]texto impreso
Castaldini, A. ; Cavallini, A. ; Fraboni, B ; Fernández Sánchez, Paloma ; Piqueras de Noriega, Javier | American Institute of Physics | 1998-02-15The deep levels present in semiconducting CdTe and semi-insulating CdTe:Cl and Cd0.8Zn0.2Te have been investigated by means of cathodoluminescence, deep level transient spectroscopy (DLTS), photo-induced current transient spectroscopy, and photo[...]texto impreso
Mártil de la Plaza, Ignacio ; González Díaz, Germán ; García, S. ; Martín Pacheco, Jaime Miguel ; Castán, E. ; Dueñas, S. | American Institute of Physics | 1995-11-01Current-voltage, small-signal measurements, and deep-level transient spectroscopy (DLTS) spectra of p-n junctions made by Mg implantation into undoped InP are described. The I-V characteristics show that the dominant conduction mechanism at forw[...]texto impreso
González Díaz, Germán ; Martín, J.M. ; Barbolla, J. ; Castán, E. ; Dueñas, S. ; Pinacho, R. ; Quintanilla, L. | American Institute of Physics | 1997-04-01In this work, we investigate the deep levels present in ion implanted and rapid thermal annealed (RTA) InP p(+)-n junctions. The samples were implanted with magnesium or coimplanted with magnesium and phosphorus. These levels were characterized [...]texto impreso
Díaz-Guerra Viejo, Carlos ; Kurdyukov, D.A. ; Piqueras de Noriega, Javier ; Sokolov, V. I. ; Zamoryanskaya, M. V. | American Institute of Physics | 2001-03-01Synthetic opals-composed of 250 nm amorphous silica spheres closed packed in a face centered cubic structure-have been infilled with silicon, platinum, and with Si and different Pt contents. The luminescent properties of these composites have be[...]texto impreso
Díaz-Guerra Viejo, Carlos ; Piqueras de Noriega, Javier ; Castaldini, A. ; Cavallini, A. ; Polent, L. | American Institute of Physics | 2003-12-15The electronic recombination properties of Mg-doped GaN have been investigated by steady state and time-resolved cathodoluminescence (TRCL) in the scanning electron microscope, photocurrent (PC) spectroscopy, and optical beam induced current (OB[...]texto impreso
The structure of defects of SiNx:H films is investigated by electron-spin resonance. It is found that a relaxation process takes place at annealing temperatures below 600 degrees C for those compositions in which the nitrogen-to-silicon ratio is[...]texto impreso
We study the dependence of the ? ? scattering phase shifts on the light quark mass in both standard and unitarized SU(2) Chiral Perturbation Theory (ChPT) to one and two loops. We then use unitarized SU(3) ChPT to study the elastic f(0)(600), k [...]texto impreso
Mártil de la Plaza, Ignacio ; González Díaz, Germán ; García, S. ; Castán, E. ; Dueñas, S. ; Fernández, M. | American Institute of Physics | 1998-01-01We have analyzed the electrical properties and bonding characteristics of SiNx:H thin films deposited at 200 degrees C by the electron cyclotron resonance plasma method. The films show the presence of hydrogen bonded to silicon (at the films wit[...]texto impreso
Mártil de la Plaza, Ignacio ; González Díaz, Germán ; Olea Ariza, Javier | American Institute of Physics | 2011-09-15A detailed study on the resulting impurity profile in Si samples implanted with high doses of Ti and subsequently annealed by pulsed-laser melting (PLM) is reported. Two different effects are shown to rule the impurity profile redistribution dur[...]texto impreso
Pérez, E. ; Dueñas, S. ; Castán, H. ; García, H. ; Bailón, L. ; Montero, Daniel ; García Hernansanz, Rodrigo ; García Hemme, Eric ; Olea Ariza, Javier ; González Díaz, Germán | American Institute of Physics | 2015-12-28The energy levels created in supersaturated n-type silicon substrates with titanium implantation in the attempt to create an intermediate band in their band-gap are studied in detail. Two titanium ion implantation doses (1013 cm-2 and 1014 cm-2)[...]texto impreso
Martínez Matos, Óscar ; Calvo Padilla, María Luisa ; Rodrigo Martín-Romo, José Augusto ; Cheben, Pavel ; Monte Muñoz de la Peña, Francisco del | American Institute of Physics | 2007-10-01We report results on the temporal evolution of the diffraction efficiency of volume holographic gratings recorded in a photopolymer glass incorporating Zr-based high refractive index species (HRIS) at molecular level. We record high spatial freq[...]texto impreso
The quasiclassical limit of the scalar nonlocal ?? -problem is derived and a quasiclassical version of the ??-dressing method is presented. Dispersionless Kadomtsev– Petviashvili (KP), modified KP, and dispersionless two- dimensional Toda latt[...]texto impreso
In this work we present a theoretical study on the thermal and electrical conductivities of quasicrystals. By considering a realistic model for the spectral conductivity we derive closed analytical expressions for the transport coefficients whic[...]texto impreso
Campoamor Stursberg, Otto Ruttwig ; Gascon, F.G. ; Peralta-Salas, D. | American Institute of Physics | 2001-12Analytical and geometrical information on certain dynamical systems X is obtained under the assumption that X is embedded into a certain real Lie algebra.texto impreso
Khaderbad, M. A. ; Dhar, S. ; Pérez García, Lucas ; Ploog, K. H. ; Melnikov, A. ; Wieck, A. D. | American Institute of Physics | 2007-08-13The authors have studied the effect of annealing on the magnetic and the structural properties of Gd focused ion beam implanted GaN samples. Molecular beam epitaxy grown GaN layers, which were implanted with 300 keV Gd^(3+) ions at room tempera[...]texto impreso
Varela del Arco, M. ; Gómez, Víctor J. ; Grandal, Javier ; Núñez Cascarejo, Arántzazu ; Naranjo, Fernando B. ; Sánchez García, M. A. ; Calleja, E. | American Institute of Physics | 2018-10This work studies the effect of four different types of buffer layers on the structural and optical properties of InGaN layers grown on Si(111) substrates and their correlation with electrical characteristics. The vertical electrical conduction [...]texto impreso
Matkovic, A. ; Guzmán, R. ; Sánchez Blázquez, P. ; Cardiel López, Nicolás ; Gorgas García, Francisco Javier | American Institute of Physics | 2009We derive ages, metallicities and [alpha/Fe] ratios for dwarf early-type galaxies (dE/dS0) in the center and a region believed to be infalling into the Coma cluster. We find that a set of metallic indices cannot be described by linear relations [...]texto impreso
Mártil de la Plaza, Ignacio ; González Díaz, Germán ; Prado Millán, Álvaro del | American Institute of Physics | 2010-06-01The influence of the silicon nitride blocking layer thickness on the interface state densities (D(it)) of HfO(2)/SiN(x):H gate-stacks on n-type silicon have been analyzed. The blocking layer consisted of 3 to 7 nm thick silicon nitride films dir[...]texto impreso
Zaldivar, M.H. ; Fernández Sánchez, Paloma ; Piqueras de Noriega, Javier ; Solís, J. | American Institute of Physics | 1999-01-15Pulsed laser treatments have been performed in GaN samples of both n- and p-type conductivity. The laser induced changes have been monitored by emissive mode and cathodoluminescence (CL) in a scanning electron microscope. Emissive mode observati[...]texto impreso
Navarro, I. ; Pulido, E. ; Crespo del Arco, Patricia ; Hernando Grande, Antonio | American Institute of Physics | 1993-03-15It is shown that the presence of highly anisotropic magnetic precipitates in a soft multiphased matrix can produce a remarkable hardening, even when the volume fraction of the precipitates is small. The exchange coupling between the matrix and t[...]texto impreso
Bruno, F. Y. ; Garcia Barriocanal, Javier ; Torija, M. ; Rivera Calzada, Alberto Carlos ; Sefrioui, Zouhair ; Leighton, C. ; León Yebra, Carlos ; Santamaría Sánchez-Barriga, Jacobo | American Institute of Physics | 2008-02-25Electrical transport properties of heteroepitaxial p-n junctions made of La_(0.8)Sr_(0.2)CoO_(3) and SrTi_(0.99)Nb_(0.01)O_(3) were studied. Junctions display highly rectifying current-voltage characteristics over a wide temperature range (20–30[...]texto impreso
Cremades Rodríguez, Ana Isabel ; Albrecht, M. ; Krinke, J. ; Dimitrov, R. ; Stutzmann, M. ; Strunk, H. P. | American Institute of Physics | 2000-03-01Combined electron beam induced current and transmission electron microscopy (TEM) measurements have been performed on both undoped and Si-doped AlGaN epitaxial films with aluminum contents x ranging from x = 0 to x = 0.79, in order to correlate [...]texto impreso
García Hemme, Eric ; Yu, K. M. ; Wahnon, P. ; González Díaz, Germán ; Walukiewicz, W. | American Institute of Physics | 2015-05-04We report the effect of d-levels of vanadium atoms on the electronic band structure of ZnO. Polycrystalline layers of Zn_(1-x)V_(x)O with 0 ? x ? 0.08 were synthesized using magnetron sputtering technique. Electrical measurements show that el[...]texto impreso
We report a study of metal-insulator-semiconductor (MIS) structures on InP. The interfacial state density and deep levels existing in MIS structures were measured by deep level transient spectroscopy (DLTS) technique. The electrical insulator pr[...]texto impreso
Díaz-Guerra Viejo, Carlos ; Piqueras de Noriega, Javier | American Institute of Physics | 1999-08-15A correlative study of the electrically active grain boundary structure of ZnO polycrystals has been carried out using a scanning electron microscope/scanning tunneling microscope (SEM/STM) combined instrument. Current imaging tunneling spectros[...]texto impreso
Rivera Calzada, Alberto Carlos ; Santamaría Sánchez-Barriga, Jacobo ; León Yebra, Carlos | American Institute of Physics | 2001-01-29We report on complex admittance measurements on ZrO_(2):Y_(2)O_(3) (YSZ) thin films in the parallel plate geometry. Highly textured YSZ thin films, grown by rf sputtering, allow measuring complex admittance free of the effect of charge blocking [...]texto impreso
Fernández Álvarez-Estrada, Ramón ; Calvo Padilla, María Luisa | American Institute of Physics | 1980The scattering of electromagnetic waves by an infinite dielectric cylinder with variable dielectric permeability presents, in general, certain mathematical difficulties regarding the construction of rigorous solutions. We give a new divergencele[...]texto impreso
Cremades Rodríguez, Ana Isabel ; Piqueras de Noriega, Javier | American Institute of Physics | 1999-02-01In the present work, electron beam induced current (EBIC) has been applied to characterize several kinds of chemical vapor deposition diamond films. Regions of enhanced carrier recombination are detected in plan-view observations of thin films a[...]texto impreso
Schmidt, Rainer ; Basu, A. ; Brinkman, A. W. ; Klusek, Z. ; Datta, P. K. | American Institute of Physics | 2005-02-14The resistance versus temperature (R–T) characteristics of NiMn_(2)O_(4+?) thermistors have been analyzed. In the literature, electron transport in manganate spinels is commonly described by a small-polaron model for nearest neighbor hopping, bu[...]texto impreso
Gómez, I. ; Domínguez-Adame Acosta, Francisco ; Díez, E. ; Bellani, V. | American Institute of Physics | 1999-04-01We study the electron transmission probability in semiconductor superlattices where the height of the barriers is modulated by a Gaussian profile. Such structures act as efficient energy band-pass filters and, contrary to previous designs, it is[...]texto impreso
The Hamiltonian for an electron in Z^2 , interacting with a perpendicular periodic magnetic field, is shown to be gauge equivalent to a periodic Hamiltonian. The wave function of the system is computed in terms of a ground state of the continuou[...]texto impreso
The generalized covariant Dirac equation for a certain five?dimensional universe is studied. If a torsion invariant is included in the free Lagrangian, it is shown that particlelike stable solutions exist having definite positive rest energy, sp[...]texto impreso
Pérez, E. ; Castán, H. ; García, H. ; Dueñas, S. ; Bailón, L. ; Montero Álvarez, Daniel ; García-Hernansanz, R. ; García Hemme, Eric ; Olea Ariza, Javier ; González Díaz, Germán | American Institute of Physics | 2015-01In the attempt to form an intermediate band in the bandgap of silicon substrates to give it the capability to absorb infrared radiation, we studied the deep levels in supersaturated silicon with titanium. The technique used to characterize the e[...]texto impreso
ailoring the structure of nanocrystalline microstructures is an important step toward controlled design of novel nanostructured materials and devices. We demonstrate how the nanocrystalline microstructure of Co-rich ribbons can be tuned by annea[...]texto impreso
Perez de Lara, Daniel ; Alija, A. ; González Herrera, Elvira María ; Martín, J. I. ; Vélez, M. ; Colino, J. L. ; Anguita,, J. V. ; Vicent López, José Luis | American Institute of Physics | 2009-03-23Superconducting a-Mo_(3)Si and Nb films have been grown on arrays of Ni nanodots. We have studied the vortex lattice dynamics close to critical temperatures. Different vortex lattice configurations are obtained with the same array unit cell. The[...]texto impreso
Masanes, Lluís ; Müller, M.P. ; Pérez García, David ; Augusiak, Remigiusz | American Institute of Physics | 2014-12We consider a very natural generalization of quantum theory by letting the dimension of the Bloch ball be not necessarily three. We analyze bipartite state spaces where each of the components has a d-dimensional Euclidean ball as state space. In[...]texto impreso
texto impreso
Tsallis, C. ; Plastino, A.R. ; Fernández Álvarez-Estrada, Ramón | American Institute of Physics | 2009-04Escort mean values or q-moments constitute useful theoretical tools for describing basic features of some probability densities such as those which asymptotically decay like power laws. They naturally appear in the study of many complex dynamica[...]texto impreso
We report on Raman scattering measurements on annealed In0.53Ga0.47As/InP layers that reveal the outdiffusion of phosphorus from, the substrate and its, possible incorporation in substitutional positions in. the In0.53Ga0.47As lattice. Raman sig[...]texto impreso
Piqueras de Noriega, Javier ; Díaz-Guerra Viejo, Carlos ; Vila Santos, María | American Institute of Physics | 2010-05-10Exchange anisotropy has been observed and investigated in single-crystalline CuO nanowires grown by thermal oxidation of Cu. The exchange bias field decreases by increasing temperature and can be tuned by the strength of the cooling field. A tra[...]texto impreso
Jones, D. B. ; Neves, R.F.C. ; Lopes, M. C. A. ; da Costa, R.F. ; Varella, M. T. do N. ; Bettega, M. H. F. ; Lima, M. A. P. ; García, G. ; Blanco Ramos, Francisco ; Brunger, M. J. | American Institute of Physics | 2015-12-14We report cross sections for electron-impact excitation of vibrational quanta in furfural, at intermediate incident electron energies (20, 30, and 40 eV). The present differential cross sections are measured over the scattered electron angular r[...]texto impreso
Chiari, Luca ; Zecca, Antonio ; Blanco Ramos, Francisco ; Brunger, M. J. | American Institute of Physics | 2016-02-28Isomerism is ubiquitous in chemistry, physics, and biology. In atomic and molecular physics, in particular, isomer effects are well known in electron-impact phenomena; however, very little is known for positron collisions. Here we report on a se[...]texto impreso
Kholmetskii, Alexsander L. ; Missevitch, Oleg V. ; Smirnov Rueda, Román ; Ivanov, Alexander R. ; Chubykalo, Andrey E. | American Institute of Physics | 2007-01-15We start with the fact that the actual consensus on the empirical verification of the standard retardation condition does not take into account the complex structure of the whole electromagnetic field in the near zone. The most rigorous and meth[...]texto impreso
González Díaz, Germán ; García Hemme, Eric ; Olea Ariza, Javier ; Pastor Pastor, David ; Bailón, L. ; Castán, H. ; Dueñas, S. ; García, H. ; Pérez, E. | American Institute of Physics | 2013-01-14Intermediate band formation on silicon layers for solar cell applications was achieved by titanium implantation and laser annealing. A two-layer heterogeneous system, formed by the implanted layer and by the un-implanted substrate, was formed. I[...]texto impreso
Wide classes of explicit solutions of the Manin-Radul and Jacobian supersymmetric KP hierarchies are constructed by using line bundles over complex supercurves based on the Riemann sphere. Their construction extends several ideas of the standard[...]texto impreso
Gómez-Ullate Otaiza, David ; Grandati, Yves ; Milson, Robert | American Institute of Physics | 2014-04Considering successive extensions of primary translationally shape invariant potentials, we enlarge the Krein-Adler theorem to mixed chains of state adding and state-deleting Darboux-Backlund transformations. It allows us to establish novel bi-l[...]texto impreso
Domínguez-Adame Acosta, Francisco ; Sánchez, A. ; Díez, E. | American Institute of Physics | 1997-01-15We study the quantum dynamics of electronic wave packets in quantum-well based semiconductor superlattices subject to an applied electric field. Using a high-accuracy numerical method, we analyze the dynamical behavior of electronic wave packets[...]texto impreso
Crespo del Arco, Patricia ; Hernando Grande, Antonio ; Garcia Escorial, A. ; Kemner, K.M. ; Harris, V. J. | American Institute of Physics | 1994-11-15The local structure and chemistry of a ferromagnetic fcc-Fe_50Cu_50 solid solution obtained through high-energy ball milling were measured before and after heat-treatment-induced decomposition using extended x-ray-absorption fine-structure measu[...]texto impreso
Ruiz de Elvira, Jacobo ; Garcia Martin, R. ; Kami?ski, Robert ; Peláez Sagredo, José Ramón | American Institute of Physics | 2011We show how the new precise data on kaon decays together with forward dispersion relations, sum rules and once- and twice-subtracted Roy equations allow for a precise analysis of ? ? scattering. The once subtracted Roy equations provide a more [...]texto impreso
We study the strange and non-strange quark mass dependence of the parameters of the f_0(600), ?(800), ?(770) and K*(892) resonances generated from elastic meson-meson scattering using unitarized one-loop Chiral Perturbation Theory. We fit simult[...]texto impreso
Nogales Díaz, Emilio ; Martin, R. V. ; O'Donnell, K. P. ; Lorenz, K. ; Alves, E. ; Ruffenach, S. ; Briot, O. | American Institute of Physics | 2006-01-16The structural properties of nanometric AlN caps, grown on GaN to prevent dissociation during high temperature annealing after Eu implantation, have been characterized by scanning electron microscopy and electron probe microanalysis. The caps pr[...]texto impreso
Piqueras de Noriega, Javier ; Alemán Llorente, Belén ; Ortega Villafuerte, Yanicet ; García Martínez, José Ángel | American Institute of Physics | 2011-07-01Fe dopedZnO nanowires,nanorods, and urchin-like nanostructures have been grown using an evaporation-deposition method with compacted mixtures of ZnS and Fe_2O_3 powders, with different Fe contents as precursors. Treatments at 950 °C under argon [...]texto impreso
Martínez Matos, Óscar ; Hernández Garay, María de la Paz ; Izquierdo, J. G. ; Vaveliuk, Pablo ; Bañares Morcillo, Luis ; Calvo Padilla, María Luisa | American Institute of Physics | 2014-07-28A procedure to characterize the induced damage and the incubation effects in volume transmission gratings under femtosecond laser pulse train illumination is presented. It was also developed a formalism that explains the damage processes. Our pr[...]texto impreso
Dhar, S. ; Kammermeier, T. ; Ney, A. ; Pérez García, Lucas ; Ploog, K. H. ; Melnikov, A. ; Wieck, A. D. | American Institute of Physics | 2006-08-07The structural and the magnetic properties of Gd-focused ion-beam-implanted GaN layers are studied. Gd^(3+) ions were uniformly implanted in molecular beam epitaxy rown GaN layers at room temperature with an energy of 300 keV at doses ranging f[...]texto impreso
Quesada, A. ; García, M. A. ; Andrés, M. ; Hernando Grande, Antonio ; Fernandez, J. F. ; Caballero, A. C. ; Martín González, M. S. ; Briones, F. | American Institute of Physics | 2006-12The origin of ferromagnetism in diluted magnetic semiconductors is still an open question, yielding a great deal of research across the world. This work focuses on the Co-Zn-O system. Room-temperature ferromagnetism is observed after a partial r[...]texto impreso
Fernández Pérez, Luis Antonio ; Martín Mayor, Víctor ; Verrocchio, P. | American Institute of Physics | 2006We report clear finite size effects in the specific heat and in the relaxation times of a model glass former at temperatures considerably smaller than the Mode Coupling transition. A crucial ingredient to reach this result is a new Monte Carlo a[...]texto impreso
Fernández Pérez, Luis Antonio ; Gordillo Guerrero, A. ; Martín Mayor, Víctor ; Ruiz Lorenzo, J. J. | American Institute of Physics | 2008We present a detailed numerical study on the effects of adding quenched impurities to a three dimensional system which in the pure case undergoes a strong first order phase transition (specifically, the ferromagnetic/paramagnetic transition of t[...]texto impreso
A deep analysis of the current-voltage (I-V) characteristics of YBa2Cu3O7 grain boundary Josephson junctions (GBJJs) allows us to go much farther than the usual calculus of the transport parameters. It is possible to construct a structural image[...]texto impreso
Ruiz Gómez, Sandra ; Serrano, A. ; Carabias,, I. ; Garc?a, M. A. ; Hernando Grande, Antonio ; Mascaraque Susunaga, Arantzazu ; Pérez García, Lucas ; González Barrio, Miguel Ángel ; Rodríguez de la Fuente, Óscar | American Institute of Physics | 2017-02-27We have used a low-energy ion bombardment to fabricate an epitaxial single-crystalline magnetite/hematite bilayer grown on Au(111). This non-conventional fabrication method involves the transformation of the upper layers of a single-crystalline [...]texto impreso
Llanes Estrada, Felipe José ; Cotanch, Steve ; General, Ignacio ; Wang, Ping | American Institute of Physics | 2008The Franck-Condon principle governing molecular electronic transitions is utilized to study heavy-quark hadron decays. This provides a direct assessment of the wavefunction of the parent hadron if the momentum distribution of the open flavor dec[...]texto impreso
Inspired by the results of Jonas, Einsenhart, Demoulin, and Bianchi on the permutability property of classical geometrical transformations of conjugate nets and its reductions-of pseudo-orthogonal, pseudo-symmetric, and pseudo-Egorov types-dress[...]texto impreso
The paper presents some basic facts concerning the formulation of the gauge invariance property of the electromagnetic field in terms of differentiable manifolds. For example, the gauge potentials are identified as differential one-forms on the [...]texto impreso
We propose an algorithm for the reduction of observational noise in chaotic multivariate time series. The algorithm is based on a maximum likelihood criterion, and its goal is to reduce the mean distance of the points of the cleaned time series [...]texto impreso
A modification of Weyl's theory of the electromagnetic field is presented, such that the usual gravitational Lagrangian becomes invariant under the corresponding definition of gauge transformation. As another advantage the problem of the we[...]texto impreso
Mártil de la Plaza, Ignacio ; González Díaz, Germán ; García, S. ; Castán, E. ; Dueñas, S. ; Fernández, M. | American Institute of Physics | 1998-01-01We have obtained Al/SiNx:H/InP metal-insulator-semiconductor devices depositing SiNx:H thin films by the electron cyclotron resonance plasma method at 200 degrees C. The electrical properties of the structures were analyzed according to capacita[...]texto impreso
Maestre Varea, David ; Cremades Rodríguez, Ana Isabel ; Piqueras de Noriega, Javier | American Institute of Physics | 2005Micro- and nanotubes, and other elongated structures of SnO_2 as wires and rods, were grown after sintering in argon flow at temperatures ranging from 1350 degrees C to 1500 degrees C. The morphology and luminescence properties of these structur[...]texto impreso
Maestre Varea, David ; Cremades Rodríguez, Ana Isabel ; Piqueras de Noriega, Javier | American Institute of Physics | 2005-02-15Sintering SnO_2 under argon flow at temperatures in the range of 1350-1500 degreesC causes the formation of wires, rods, and tubes on the sample surface. At high temperatures of the mentioned range, microwires with lengths of hundreds of microns[...]texto impreso
Carcelen, V. ; Hidalgo Alcalde, Pedro ; Rodríguez Fernández, J. ; Dieguez, E. | American Institute of Physics | 2010-05-01The II-VI compound semiconductor cadmium zinc telluride (CZT) is very useful for room temperature radiation detection applications. In the present research, we have successfully grown Bi doped CZT single crystals with two different zinc concentr[...]texto impreso
Carcelen, V. ; Hidalgo Alcalde, Pedro ; Rodríguez Fernández, J. ; Dieguez, E. | American Institute of Physics | 2010-05-01The II-VI compound semiconductor cadmium zinc telluride (CZT) is very useful for room temperature radiation detection applications. In the present research, we have successfully grown Bi doped CZT single crystals with two different zinc concent[...]texto impreso
Antoranz Canales, Pedro ; Miranda Pantoja, José Miguel ; Sebastián Franco, José Luis ; Cámara, M. ; Fonseca González, Mª Victoria | American Institute of Physics | 2005-05-01We report on this work a model to accurately predict the electrical behavior of double-heterostructure GaN/SiC blue light-emitting diodes up to microwave frequencies. A procedure to extract the series resistance (R-s) from the reflection coeffic[...]texto impreso
Marín Palacios, María Pilar ; Marcos, M. ; Hernando Grande, Antonio | American Institute of Physics | 2010-06-28In this letter, we report the experimental work carried out to study and improve the magnetomechanical coupling on magnetic microwires. A good magnetoelastic response, with magnetoelastic coupling factor k=0.43, has been obtained by control of b[...]texto impreso
Mártil de la Plaza, Ignacio ; González Díaz, Germán ; Lucía Mulas, María Luisa ; San Andres Serrano, Enrique | American Institute of Physics | 2007-08-15Hafnium oxide films were deposited by high pressure reactive sputtering using different deposition pressures and times. The composition, morphology, and optical properties of the films, together with the sputtering process growth kinetics were i[...]texto impreso
Si implantations into undoped In0.53Ga0.47As have been carried out to obtain n-layers suitable for device applications. Different doses and energies have been analyzed. After rapid thermal annealing at 850-875 degrees C for 10-20 s, electrical a[...]texto impreso
Mártil de la Plaza, Ignacio ; González Díaz, Germán ; Olea Ariza, Javier ; San Andres Serrano, Enrique | American Institute of Physics | 2010-05-15In this paper, we present a detailed characterization of high quality layers of Si implanted with Ti at high doses. These layers are intended to the formation of an intermediate band (IB) solar cell. The main requirement to obtain an IB material[...]texto impreso
Martínez Arnáiz, R. M. ; Maldonado, J. ; Montes Gutiérrez, David ; Eiroa, C. ; Montesinos, B. ; Ribas, I. ; Solano, E. | American Institute of Physics | 2009We present the most recent results of our ongoing long-term high resolution spectroscopic study of nearby (d ? 25 pc) FGK stars which aim is to characterize the local properties of the Galaxy, in particular the star-formation history. A through [...]texto impreso
Ruiz Gómez, Sandra ; González Barrio, Miguel Ángel ; Mascaraque Susunaga, Arantzazu ; Pérez García, Lucas ; Serrano, Aída ; Guerrero, Rubén ; Muñoz, Manuel ; Lucas, Irene ; Foerster, Michael ; Aballe, Lucía | American Institute of Physics | 2018-10-22The spin Hall effect (SHE) provides an efficient tool for the production of pure spin currents, essentially for the next generation of spintronics devices. Giant SHE has been reported in Cu doped with 0.5% Bi grown by sputtering, and larger valu[...]texto impreso
Díaz-Guerra Viejo, Carlos ; Piqueras de Noriega, Javier | American Institute of Physics | 1996-07-15Cathodoluminescence (CL) of YBa_2Cu_3O_(7-x) single crystals has been investigated in the scanning electron microscope, Some regions of the crystals, generally related to steps or other growth features, show enhanced CL Intensity. Spectra show t[...]texto impreso
Junge, M. ; Palazuelos Cabezón, Carlos ; Parcet, J. ; Perrin, M. | American Institute of Physics | 2015-02We obtain hypercontractivity estimates for a large class of semigroups defined on finite-dimensional matrix algebras Mn. These semigroups arise from Poisson-like length functions ? on Zn × Zn and provide new hypercontractive families of quantum [...]texto impreso
Crespo del Arco, Patricia ; Marín, P. ; Hernando Grande, Antonio | American Institute of Physics | 2000-05-01We present experimental results on the hysteresis and relaxation of Fe/Ba hexaferrite composite samples prepared by ball milling starting from precursor Fe and Ba hexaferrite particles. Our results show that, for maximum applied fields of up to [...]texto impreso
Schmidt, Rainer ; Mayrhofer, Patrick ; Schmid, Ulrich ; Bittner, Achim | American Institute of Physics | 2019-02-26In this work, a comprehensive characterization of metal-insulator-semiconductor structures by impedance spectroscopy is demonstrated for the case of electrically insulating, highly c-axis oriented, 600 nm sputter-deposited AlN films on n-Si subs[...]texto impreso
Ruiz-Valdepeñas Martín de Almagro, Luis ; Vélez, M. ; Valdés Bango, F. ; Álvarez Prado, L.M. ; García Alonso, F.J. ; Martín, J.I. ; Navarro Palma, Elena ; Alameda, J.M. ; Vicent López, José Luis | American Institute of Physics | 2014-06-07Magnetization reversal processes have been studied in hybrid magnetic/superconducting Nd-Co/Nb bilayers by the comparison of out-of-plane magnetic hysteresis loops and superconducting phase diagrams as a function of magnetic layer thickness and [...]texto impreso
Temperature dependent in-plane impedance spectroscopy measurements were carried out in order to analyze the charge transport properties of functional oxide NiMn_(2)O_(4) negative temperature coefficient thermistor films deposited via aerosol dep[...]texto impreso
Bartolomé Vílchez, Javier ; Hidalgo Alcalde, Pedro ; Maestre Varea, David ; Cremades Rodríguez, Ana Isabel ; Piqueras de Noriega, Javier | American Institute of Physics | 2014-04-21Electric field induced mechanical resonances of In2O3 microrods are studied by in-situ measurements in the chamber of a scanning electron microscope. Young's moduli of rods with different cross-sectional shapes are calculated from the resonance [...]texto impreso
Liu, Yaohua ; Tornos, J. ; te Velthuis, S. G. E. ; Freeland, J. W. ; Zhou, H. ; Steadman, P. ; Bencok, P. ; León Yebra, Carlos ; Santamaría Sánchez-Barriga, Jacobo | American Institute of Physics | 2016-04In artificial multiferroics hybrids consisting of ferromagnetic La_(0.7)Sr_(0.3)MnO_(3) (LSMO) and ferroelectric BaTiO_(3) epitaxial layers, net Ti moments are found from polarized resonant soft x-ray reflectivity and absorption. The Ti dichroic[...]texto impreso
Garcia, J. A. ; Remon, A. ; Piqueras de Noriega, Javier | American Institute of Physics | 1987-10-01The effect of the addition of Bi and Mn on the photoluminescence from ZnO ceramics has been investigated. The effect of the presence of impurities on the green luminescence band can be compared to the effect of oxidizing treatments. A narrow gre[...]texto impreso
We have measured the electrical and optical properties of blue light-emitting diodes (LEDs) based on III-V nitrides. The current-voltage characteristic is described by means of the relation I = I-0 exp(alpha V). In this equation alpha is tempera[...]texto impreso
Mártil de la Plaza, Ignacio ; González Díaz, Germán ; Prado Millán, Álvaro del ; San Andres Serrano, Enrique | American Institute of Physics | 2004-05-15The influence of H on the composition and atomic concentrations of Si, O, and N of plasma deposited SiOxNyHz films was investigated. The bonding scheme of H was analyzed by Fourier-transform infrared spectroscopy. The composition and absolute co[...]texto impreso
Mártil de la Plaza, Ignacio ; González Díaz, Germán ; Prado Millán, Álvaro del | American Institute of Physics | 2008-11-01Al/HfO(2)/SiN(x):H/n-Si metal-insulator-semiconductor capacitors have been studied by electrical characterization. Films of silicon nitride were directly grown on n-type silicon substrates by electron cyclotron resonance assisted chemical vapor [...]texto impreso
The possibility of downhill instead of two-state folding for proteins has been a very controversial topic which arose from recent experimental studies. From the theoretical side, this question has also been accomplished in different ways. Given [...]texto impreso
Cremades Rodríguez, Ana Isabel ; Narayanan, V.C. ; Piqueras de Noriega, Javier ; Lima, A.P. ; Ambacher, O. ; Stutzmann, M. | American Institute of Physics | 2001-11-01Plasma-induced molecular beam epitaxial AlInGaN heterostructures have been characterized by spatial resolved cathodoluminescence and x-ray energy dispersive microanalysis. Competitive incorporation of Al and In has been observed, with the format[...]texto impreso
Kodama, Y. ; Konopelchenko, Boris ; Martínez Alonso, Luis ; Medina Reus, Elena | American Institute of Physics | 2005-11A general scheme for determining and studying hydrodynamic type systems describing integrable deformations of algebraic curves is applied to cubic curves. Lagrange resolvents of the theory of cubic equations are used to derive and characterize t[...]texto impreso
Jones, D. B. ; da Costa, R.F. ; Varella, M. T. do N. ; Bettega, M. H. F. ; Lima, M. A. P. ; Blanco Ramos, Francisco ; García, G. ; Brunger, M. J. | American Institute of Physics | 2016-04-14We report absolute experimental integral cross sections (ICSs) for electron impact excitation of bands of electronic-states in furfural, for incident electron energies in the range 20-250 eV. Wherever possible, those results are compared to corr[...]texto impreso
Linearized hydrodynamic equations for a nonuniform anisotropic fluid are obtained from the exact Mori-Zwanzig equations for the conserved densities. In the particular case of a two-phase system with a planar equilibrium interface, these equation[...]texto impreso
Mártil de la Plaza, Ignacio ; González Díaz, Germán ; Olea Ariza, Javier | American Institute of Physics | 2012-12-01We have analyzed by means of Rutherford backscattering spectrometry (RBS) the Ti lattice location and the degree of crystalline lattice recovery in heavily Ti implanted silicon layers subsequently pulsed laser melted (PLM). Theoretical studies h[...]texto impreso
González López, Artemio ; Hernández Heredero, Rafael ; Beffa, Gloria Marí | American Institute of Physics | 1997-11In this paper we find an explicit formula for the most general vector evolution of curves on RPn?1 invariant under the projective action of SL(n, R). When this formula is applied to the projectivization of solution curves of scalar Lax operators[...]texto impreso
Mialdun, A. ; Sechenyh, V. ; Legros, J. C. ; Ortiz de Zárate Leira, José María ; Shevtsova, V. | American Institute of Physics | 2013-09-14We present a comprehensive analysis of experimental results obtained for Fickian diffusion in the benchmark ternary liquid mixture of 1,2,3,4-tetrahydronaphthalene, isobutylbenzene, and dodecane (nC(12)) with equal mass fractions. Isothermal dif[...]texto impreso
Mártil de la Plaza, Ignacio ; García Hemme, Eric ; García Hernansanz, Rodrigo ; González Díaz, Germán ; Olea Ariza, Javier ; Prado Millán, Álvaro del | American Institute of Physics | 2012Ti supersaturated Si layers with two different thicknesses have been obtained on the top of a Si substrate by means of ion implantation and pulsed laser melting processes. Time-of-flight Secondary Ion Mass spectrometry (ToF-SIMS) measurements sh[...]texto impreso
Velasco, J. L. ; Castejón, F. ; Fernández Pérez, Luis Antonio ; Martín Mayor, Víctor ; Tarancón, A. | American Institute of Physics | 2008The ion Drift Kinetic Equation (DKE) which describes the ion coUisional transport is solved for the TJ-II device plasmas. This non-linear equation is computed by peribrming a mean field iterative calculation. In each step of the calculation, a F[...]texto impreso
Campoamor Stursberg, Otto Ruttwig ; Rausch de Traubenberg, Michel | American Institute of Physics | 2008We study and classify kinematical algebras which appear in the framework of Lie superalgebras or Lie algebras of order three. All these algebras are related through generalised Inonü-Wigner contractions from either the orthosymplectic superalgeb[...]texto impreso
A Klein–Gordon field with a derivative fourth order self?coupling is studied. It is shown that the kinks of the model form singlets, doublets, or triplets of electric charge, according to the values of the coupling constants.texto impreso
Mártil de la Plaza, Ignacio ; González Díaz, Germán ; Olea Ariza, Javier | American Institute of Physics | 2009-09-01We have studied the laser thermal annealing (LTA) effects on single crystal GaP. The samples have been analyzed by means of Raman spectroscopy, glancing incidence x-ray diffraction (GIRXD), and transmission electron microscopy (TEM) measurements[...]texto impreso
Gálvez, F. ; Valle, J. del ; Gómez Gutiérrez, Alicia ; González Herrera, Elvira María ; Navarro Palma, Elena ; Vicent López, José Luis ; Soriano, N. ; Mora, B. ; Rollano, V. ; Gargiani, P. | American Institute of Physics | 2020-06-01The development of multilayered materials with engineered magnetic properties compels a deep knowledge of physical properties at the atomic scale. The magnetic anisotropy is a key property in these materials. This work accounts for the magnetic [...]texto impreso
Li, W. B. ; Zhang, K. J. ; Sengers, Jan V. ; Gammon, R. W. ; Ortiz de Zárate Leira, José María | American Institute of Physics | 2000-05-22We have performed light-scattering measurements in dilute and semidilute polymer solutions of polystyrene in toluene when subjected to stationary temperature gradients. Five solutions with concentrations below and one solution with a concentrati[...]texto impreso
The DaveyStewartson equation is considered from the point of view of the bilinear formalism of the Kyoto school. Multidromion solutions are constructed in terms of free fermions and their asymptotic properties are characterized. The dynamical pr[...]texto impreso
We study some global properties of a self?interacting Dirac field which has been used to construct a classical stable model of the hydrogen atom. It is shown that the normalization condition produces the correct values of both charge and spin an[...]texto impreso
Slow nanocrystallization driving dynamics can be affected by the combination of two factors: sample residual stresses and sample geometry. This effect is evidenced at the initial stages of nanocrystallization of amorphous CoFeSiBCuNb magnetic mi[...]texto impreso
Domínguez-Adame Acosta, Francisco ; Fernández Sánchez, Paloma ; Piqueras de Noriega, Javier ; Prieto, P. | American Institute of Physics | 1992-03-15Visible and near infrared cathodoluminescence of Bi_2Sr_2CaCu_2O_x and YBa_2Cu_3O_(7-x) films is investigated in the scanning electron microscope. In particular, possible analogies in the cathodoluminescence of both systems have been analyzed. T[...]texto impreso
Zaldivar, M.H. ; Fernández Sánchez, Paloma ; Piqueras de Noriega, Javier | American Institute of Physics | 1998-01-01Cathodoluminescence (CL) in the scanning electron microscope is used to investigate the nature of defects responsible for the luminescence associated with round and hexagonal-like topographic features of GaN:Si films. Round hillocks of the size [...]texto impreso
Cremades Rodríguez, Ana Isabel ; Piqueras de Noriega, Javier | American Institute of Physics | 1995-09-01The effect of laser cutting on the structure of a chemical vapor deposited diamond film has been investigated by cathodoluminescence (CL) in the scanning electron microscope. The variation of particle morphology and CL spectra as a function of t[...]texto impreso
Cremades Rodríguez, Ana Isabel ; Piqueras de Noriega, Javier ; Remon, A. ; Garcia, J. A. ; Santos, M. T. ; Dieguez, E. | American Institute of Physics | 1998-06-15Changes on the defect structure of Bi12GeO20 (BGO) and Bi12SiO20 (BSO) crystals induced by thermal treatments and laser irradiation have been studied by means of cathodoluminescence in the scanning electron microscope. The results have been comp[...]texto impreso
We review the N_c and m_? dependence of the rho(770) and ? (or f_0(600) resonances generated with the Inverse Amplitude Method. The ? N_c behavior is at odds with being dominantly a q?q? state, but there is a hint of a subdominant q?q?o componen[...]texto impreso
Rivero, G. ; Crespo del Arco, Patricia ; Pulido, E ; Garcia-Escorial, A. ; Hernando Grande, Antonio ; Vázquez, M. ; Vallet, M. ; Gonzalez-Calbet, J. | American Institute of Physics | 1991-04-15The specific magnetic moment, coercive force, anisotropy field, and saturation magnetostriction constant have been measured in Co(1-x)P(x) amorphous ribbons with 0.04 less-than-or-equal-to x less-than-or-equal-to 0.27. Differential scanning calo[...]texto impreso
Marín, P. ; López, M. ; Vlad, A. ; Hernando Grande, Antonio ; Ruiz González, M. L: ; González Calbet, J. M. | American Institute of Physics | 2006-07-17We present the possibility of tuning the nanocrystalline microstructure of Co-rich samples by magnetic field annealing. Custom assembly of nucleated grains, aligned in the field direction, has been observed by means of high resolution transmissi[...]texto impreso
Joshi, Amish G ; Kryukov, Sergiy A. ; De Long, Lance E. ; González Herrera, Elvira María ; Navarro Palma, Elena ; Villegas, Javier E. ; Vicent López, José Luis | American Institute of Physics | 2007-05-01We report vibrating reed and superconducting quantum interference device magnetometer data that exhibit prominent dips or oscillations of the superconducting (SC) onset temperature, Delta T(C)(H)approximate to 0.01-0.7 K, for a [Nb(23 nm)/Ni(5 n[...]texto impreso
Nemes, Norbert Marcel ; Visani, C. ; León Yebra, Carlos ; Gárcia Hernández, M. ; Simón, F. ; Feher, T. ; te Velthuis, S. G. E. ; Hoffmann, A. ; Santamaría Sánchez-Barriga, Jacobo | American Institute of Physics | 2010-07-19We report a memory concept utilizing ferromagnet/superconductor/ferromagnet La_(0.7)Ca_(0.3)MnO_(3)/YBa_(2)Cu_(3)O_(7)/La_(0.7)Ca_(0.3)MnO_(3) thin film hybrid structures. The orientation of the magnetic field with respect to the ferromagnetic e[...]texto impreso
Navarro Palma, Elena ; Vélez, M. ; Huttel, Y. ; Pérez Junquera, A. ; Martín, J. Y. ; Lima, O. F. de ; Cebollada, A. ; Alameda, J. M. ; Vicent López, José Luis | American Institute of Physics | 2009-02-01Shifted hysteresis loops characteristic of the exchange bias effect between a ferromagnet and an antiferromagnet are demonstrated in structures formed by a 2.5 nm Cr layer deposited on top of an array of Fe nanoislands (Cr/Fe-nanoislands). This [...]texto impreso
Pérez de Lara, David ; Castaño, F. J. ; Ng, B. G. ; Körner, H. S. ; Dumas, R. K. ; González Herrera, Elvira María ; Liu, Kai ; Ross,, C. A. ; Schuller, Ivan K. ; Vicent López, José Luis | American Institute of Physics | 2011-10-31Strong superconducting pinning effects are observed from magnetic landscapes produced by arrays of circular rings with varying magnetic remanent states. The collective and the background pinning of superconducting Nb films is strongly enhanced b[...]texto impreso
Lopez Maldonado, K. L. ; Presa Muñoz del Toro, Patricia de la ; Flores Tavizon, E. ; Farias Mancilla, J: R: ; Matutes Aquino, J. A. ; Hernando Grande, Antonio ; Elizalde Galindo, J. T. | American Institute of Physics | 2013-05-07Magnetite nanostructured powder samples were synthesized by aging chemical method. Phase, structural, and magnetic properties were characterized. X-ray diffraction patterns showed cubic magnetite pure phase, with average crystallite size, [...]texto impreso
Díaz-Guerra Viejo, Carlos ; Pérez García, Lucas ; Piqueras de Noriega, Javier ; Chioncel, M. F. | American Institute of Physics | 2009-11-15Magnetic transitions in single-crystal alpha-F_2O_3 (hematite) nanowires, grown by thermal oxidation of iron powder, have been studied in the range of 5-1023 K with a superconducting quantum interference device below room temperature and with a [...]texto impreso
Valle Granda, Javier del ; Gómez, A. ; González, E. M. ; Vicent López, José Luis | American Institute of Physics | 2016-10-24In order to compare magnetic and non-magnetic pinning, we have nanostructured two superconducting films with the regular arrays of pinning centers: Cu (non-magnetic) dots in one case and Py (magnetic) dots in the other. For low applied magnetic [...]texto impreso
Prieto, P. ; Vivas, P. ; Campillo, G. ; Baca, E. ; Castro, L. F. ; Varela del Arco, María ; Ballesteros, C. ; Villegas, J. E. ; Arias Serna, Diego ; León Yebra, Carlos ; Santamaría Sánchez-Barriga, Jacobo | American Institute of Physics | 2001-06-15We report on the magnetic and superconducting properties of La_(0.7)Ca_(0.3)MnO_(3)/YBa_(2)Cu_(3)O_(7) (LCMO/YBCO) superlattices. For a constant LCMO layer thickness of 6 unit cells (u.c.), resistance and susceptibility measurements show superco[...]texto impreso
Lopez Maldonado, K. L. ; Vazquez Zubiate, L. ; Presa Muñoz del Toro, Patricia de la ; Matutes Aquino, J. A. ; Elizalde Galindo, J. T. | American Institute of Physics | 2014-05-07Manganese and Zinc ferrites were prepared by solid state reaction. The resulting powders were pressed into pellets and heat treated at 1100 ?C. The samples were characterized by using X-ray diffraction, pure phases of zinc ferrite (ZnFe²O?) and [...]texto impreso
Guerrero, E. ; Munoz-Marquez, M. A. ; Fernández, A. ; Crespo del Arco, Patricia ; Hernando, A. ; Lucena, R. ; Conesa, J. C. | American Institute of Physics | 2010-03-15In the last years, the number of studies performed by wholly independent research groups that confirm the permanent magnetism, first observed in our research lab, for thiol-capped Au nanoparticles (NPs) has rapidly increased. Throughout the year[...]texto impreso
Mathematics is the language of science however, in secondary and high school education students are not made aware of the strong implications behind this statement. This is partially caused because mathematical training and the modelling of natu[...]texto impreso
We present a theoretical analysis of quasicrystals (QCs) as potential thermoelectric materials. We consider a self-similar density of states model and extend the framework introduced in [G. D. Mahan and J. O. Sofo, Proc. Natl. Acad. Sci. U.S.A. [...]texto impreso
Kholmetskii, Alexsander L. ; Missevitch, Oleg V. ; Smirnov Rueda, Román | American Institute of Physics | 2007We start with the general approach based on conventional solutions to Maxwell's equations and show that in the near zone of macroscopic electromagnetic sources the electromotive force produced in receiving loop antenna is intimately linked to th[...]texto impreso
Vázquez Peñas, José R. ; Ortiz de Zárate Leira, José María ; Khayet Souhaimi, Mohamed | American Institute of Physics | 2008-08-15We present experimental results of the thermal conductivity of several nanofluids prepared by dispersing nanoparticles of SiO(2) and CuO in water and ethylene glycol at various concentrations up to approximate to 5% in mass fraction. The measure[...]texto impreso
Roldán, É. ; Martínez, I. A. ; Dinis Vizcaíno, Luis Ignacio ; Rica, R.A. | American Institute of Physics | 2014-06-09We report on the measurement of the average kinetic energy changes in isothermal and nonisothermal quasistatic processes in the mesoscale, realized with a Brownian particle trapped with optical tweezers. Our estimation of the kinetic energy chan[...]texto impreso
Using a field theoretical, QCD inspired Hamiltonian formulated in the Coulomb gauge, relativistic many-body calculations are reported which reproduce the semiquantitative features of the observed meson and lattice glueball spectrums. Dynamical c[...]texto impreso
Lucía Mulas, María Luisa ; Sánchez Quesada, Francisco ; Santamaría Sánchez-Barriga, Jacobo ; Sefrioui, Zouhair ; Varela del Arco, María ; Arias Serna, Diego ; Loos, G. ; Navacerrada, M.A. | American Institute of Physics | 1998-12-07We have studied the effect of He+ irradiation on the electrical resistivity and Curie temperature of ferromagnetic SrRuO3 thin films. An evolution from metallic to insulating behavior is observed when He+ ion fluence is increased, suggesting a m[...]texto impreso
Mártil de la Plaza, Ignacio ; González Díaz, Germán ; Prado Millán, Álvaro del ; San Andres Serrano, Enrique | American Institute of Physics | 2003-07-15The effect of rapid thermal annealing (RTA) processes on the structural properties of SiOxNyHz films was investigated. The samples were deposited by the electron cyclotron resonance plasma method, using SiH4, O-2 and N-2 as precursor gases. For [...]texto impreso
Carmona Tejero, Noemi ; Bouzas, V. ; Jiménez de la Morena, J. ; García, M. A. | American Institute of Physics | 2010We present here some miniaturised devices designed for the detection of nanorods in water and blood media. The devices use light emitting diodes as monochromatic light sources and Si photodiodes for detection. Devices working on transmission mod[...]texto impreso
The dynamics of thermoplastic-photoconductor films is reviewed. A theory of thermoplastic film deformation is presented for a three-layer structure in air with modified boundary conditions. The amplitude of the deformation A versus the spatial f[...]texto impreso
Cabero Piris, M. ; Nagy, K. ; Gallego, F. ; Sander, A. ; Rio, M. ; Cuellar, F.A. ; Tornos, J. ; Hernández Martín, David ; Nemes, Norbert Marcel ; Mompean, F. ; Gárcia Hernández, M. ; Rivera Calzada, Alberto Carlos ; Sefrioui, Zouhair ; Reyren, N. ; Feher, T. ; Varela del Arco, María ; León Yebra, Carlos ; Santamaría Sánchez-Barriga, Jacobo | American Institute of Physics | 2017-09Controlling magnetic anisotropy is an important objective towards engineering novel magnetic device concepts in oxide electronics. In thin film manganites, magnetic anisotropy is weak and it is primarily determined by the substrate, through indu[...]texto impreso
Jimeno Romero, Pablo ; Ruiz Cembranos, José Alberto ; Cruz Dombriz, Álvaro de la | American Institute of Physics | 2012-07In the context of f(R) modified gravity theories we determine that the black holes existence is determined by the sign of a parameter dependent of the mass, the charge, the spin and the scalar curvature. We obtain the different astrophysical obj[...]texto impreso
Jaulent, Marcel ; Manna, Miguel A. ; Martínez Alonso, Luis | American Institute of Physics | 1989-08A multiseries integrable model (MSIM) is defined as a family of compatible flows on an infinite-dimensional Lie group of N-tuples of formal series around N given poles on the Riemann sphere. Broad classes of solutions to a MSIM are characterized[...]texto impreso
We review our work on the ? and ? resonances derived from the Inverse Amplitude Method. In particular, we study the leading 1/N_c behavior of the resonances masses and widths and their evolution with changing m_?. The 1/Nc expansion gives a clea[...]texto impreso
Ngai, K. L. ; Lunkenheimer, P. ; León Yebra, Carlos ; Schneider, U. ; Brand, R. ; Lodl, A. | American Institute of Physics | 2001-07-15Previous dielectric relaxation measurements of glycerol and propylene carbonate and new results on propylene glycol performed below the conventional glass transition temperatures T_(g) after long periods of aging all show that the excess wing (a[...]texto impreso
Nogales Díaz, Emilio ; Joachimsthaler, I. ; Heiderhoff, R. ; Piqueras de Noriega, Javier ; Balk, L.J. | American Institute of Physics | 2002-07-15Near-field cathodoluminescence (NFCL) has been used to characterize hydride vapor phase epitaxy grown n-GaN films. This technique can obtain high resolution luminescence images and perform local measurements of the diffusion length for minority [...]texto impreso
Analysis of the question whether or not a given dynamical system has closed trajectories is of great importance for applications and represents independent theoretical interest. The authors give a new geometrical proof of the extension of the Be[...]texto impreso
We say that several scalar time series are dynamically coupled if they record the values of measurements of the state variables of the same smooth dynamical system. We show that much of the information lost due to measurement noise in a target t[...]texto impreso
Fernández Pérez, Luis Antonio ; Martín Mayor, Víctor ; Muñoz Sudupe, Antonio ; Yllanes, D. ; otros, ... | American Institute of Physics | 2009The out of equilibrium evolution for an Edwards?Anderson spin glass is followed for a tenth of a second, a long enough time to let us make safe predictions about the behaviour at experimental scales. This work has been made possible by Janus, an[...]texto impreso
Fernández Álvarez-Estrada, Ramón ; Pastor, I. ; Guasp, J. ; Castejón, F. | American Institute of Physics | 2012-06The classical nonlinear incoherent Thomson scattering power spectrum from a single relativistic electron with incoming laser radiation of any intensity, investigated numerically by the present authors in a previous publication, displayed both an[...]texto impreso
In this paper we analyze Abelian diagonal orthogonally transitive space–times with spacelike orbits for which the matter content is a stiff perfect fluid. The Einstein equations are cast in a suitable form for determining their geodesic complete[...]