Información del autor
Autor Maciá Barber, Enrique Alfonso |
Documentos disponibles escritos por este autor (55)
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Landauro, C.V. ; Maciá Barber, Enrique Alfonso ; Solbrig, H. | American Physical Society | 2003-05-01We investigate by analytical means the electronic transport properties of approximants and quasicrystals. The spectral resistivity is modeled by Lorentz functions in agreement with realistic ab initio calculations (linear muffin-tin orbital basi[...]texto impreso
We numerically investigate the effects of inhomogeneities in the energy spectrum of aperiodic semiconductor superlattices, focusing our attention on Thue-Morse and Fibonacci sequences. In the absence of disorder, the corresponding electronic spe[...]texto impreso
Aperiodic order plays a very significant role in biology, as it determines most informative content of genomes. Amongst the various physical, chemical or biological phenomena that might be inferred from sequence correlations, charge transfer pro[...]texto impreso
Quasicrystals are a class of ordered solids made of typical metallic atoms but they do not exhibit the physical properties that usually signal the presence of metallic bonding, and their electrical and thermal transport properties resemble a mor[...]texto impreso
In this work, we show that the fundamental structure of the electronic energy spectrum of binary Fibonacci quasicrystals can be decomposed in terms of two main contributions, stemming from two related characteristic symmetries. The algebraic app[...]texto impreso
The thermoelectric power of trimer oligonucleotides connected in between metallic contacts at different temperatures is theoretically studied. The obtained analytical expressions reveal the existence of important resonance effects leading to a s[...]texto impreso
In this work we present a prospective study on the possible use of certain quasicrystalline alloys in order to improve the efficiency of segmented thermoelectric generators. To this end, we obtain a closed analytical expression for their compati[...]texto impreso
Maciá Barber, Enrique Alfonso ; Triozon, François ; Roche, Stephan | American Physical Society | 2005-03We report on theoretical results about contact-dependent effects and tunneling currents through DNA molecules. A tetranucleotide PolyGACT chain, connected in between metallic contacts, is studied as a generic case, and compared to other periodic[...]texto impreso
Domínguez-Adame Acosta, Francisco ; Maciá Barber, Enrique Alfonso ; Sánchez, Angel | American Physical Society | 1993-09-01Normal modes of one-dimensional disordered chains with two couplings, one of them assigned at random to pairs in an otherwise perfect chain, are investigated. We diagonalize the dynamical matrix to find the normal modes and to study their spatia[...]texto impreso
The thermoelectric performance of PolyG-PolyC and PolyA-PolyT double-stranded chains connected between organic contacts at different temperatures is theoretically studied on the basis of an effective model Hamiltonian. The obtained analytical ex[...]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
Díez, E. ; Domínguez-Adame Acosta, Francisco ; Maciá Barber, Enrique Alfonso ; Sánchez, A. | American Physical Society | 1996-12-15We present a detailed study of the dynamics of electronic wave packets in Fibonacci semiconductor superlattices, both in flat band conditions and subject to homogeneous electric fields perpendicular to the layers. Coherent propagation of electro[...]texto impreso
Maciá Barber, Enrique Alfonso ; Domínguez-Adame Acosta, Francisco ; Sánchez, Angel | American Physical Society | 1994-04-01We derive a discrete Hamiltonian describing a Fibonacci superlattice in which the electronic potential is taken to be an array of equally spaced delta potentials, whose strengths modulate the chemical composition in the growth direction. In this[...]texto impreso
In this work we consider the combined effect of helical structure and base-pair twist motion on charge transfer through duplex DNA at low temperatures. We present a fully analytical treatment of charge-lattice coupled dynamics in terms of neares[...]texto impreso
We consider a class of synthetic DNA molecules based on a quasiperiodic arrangement of their constituent nucleotides. Making use of a two-step renormalization scheme the double-stranded DNA molecule is modeled in terms of a one-dimensional effec[...]texto impreso
Domínguez-Adame Acosta, Francisco ; Maciá Barber, Enrique Alfonso ; Méndez Martín, Bianchi | Elsevier Science BV | 1994-10-31We study the electronic structure of a new type of Fibonacci superlattice based on Si delta-doped GaAs. Assuming that delta-doped layers are equally spaced, quasiperiodicity is introduced by selecting two different donor concentrations and arran[...]texto impreso
Domínguez-Adame Acosta, Francisco ; Méndez Martín, Bianchi ; Maciá Barber, Enrique Alfonso | IOP publishing ltd | 1994-03The electron dynamics and the density of states of both single and periodic Si delta-doped GaAs subject to an applied electric field are studied theoretically. The space charge potential due to delta-doping is obtained by means of the semiclassi[...]texto impreso
A detailed study of charge transport properties of synthetic and genomic DNA sequences is reported. Genomic sequences of the Chromosome 22, lambda-bacteriophage, and D1s80 genes of Human and Pygmy chimpanzee are considered in this work, and comp[...]texto impreso
In this work we extend the algebraic approach introduced in the context of general Fibonacci systems [E. Maciá and F. Domínguez-Adame, Phys. Rev. Lett. 76, 2957 (1996)] to analytically study the transmission coefficient of a subset of states in [...]texto impreso
Maciá Barber, Enrique Alfonso ; Domínguez-Adame Acosta, Francisco ; Sánchez, Angel | American Physical Soc | 1994-08We study the relationship between the electronic spectrum structure and the configurational order of one-dimensional quasiperiodic systems. We take the Fibonacci case as a specific example, but the ideas outlined here may be useful to accurately[...]texto impreso
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Sánchez, Angel ; Maciá Barber, Enrique Alfonso ; Domínguez-Adame Acosta, Francisco | American Physical Society | 1994-06-01We consider the electron dynamics and transport properties of one-dimensional continuous models with random, short-range correlated impurities. We develop a generalized Poincare map formalism to cast the Schrodinger equation for any potential in[...]texto impreso
Sánchez, A. ; Domínguez-Adame Acosta, Francisco ; Maciá Barber, Enrique Alfonso | American Physical Society | 1995-01-01Incoherent transport of excitations in one-dimensional disordered lattices with pairs of traps placed at random is studied by numerically solving the corresponding aster equation. Results are compared to the case of lattices with the same concen[...]texto impreso
Maciá Barber, Enrique Alfonso ; Domínguez-Adame Acosta, Francisco | American Physical Society | 1994-12-15Exciton optical absorption in self-similar aperiodic one-dimensional systems is considered, focusing our attention on Thue-Morse and Fibonacci lattices as canonical examples. The absorption line shape is evaluated by solving the microscopic equa[...]texto impreso
Domínguez-Adame Acosta, Francisco ; Méndez Martín, Bianchi ; Sánchez, A. ; Maciá Barber, Enrique Alfonso | American Physical Society | 1994-02-01Numerical investigations of the trapping of Frenkel excitons in one-dimensional lattices with interstitial traps randomly placed in pairs are presented. The probabilities of finding the exciton both in the q = 0 mode P(t) and in any mode Q(t) ha[...]