Información del autor
Autor Relaño Pérez, Armando |
Documentos disponibles escritos por este autor (48)
![](./images/expand_all.gif)
![](./images/collapse_all.gif)
![Selecciones disponibles](./images/orderby_az.gif)
![]()
texto impreso
For a certain class of isolated quantum systems, we report the existence of irreversible processes in which the energy is not dissipated. After a closed cycle in which the initial energy distribution is fully recovered, the expectation value of [...]![]()
texto impreso
Gómez Gómez, José María ; Molina, R. A. ; Relaño Pérez, Armando ; Retamosa Granado, Joaquín | American Physical Society | 2002-09The main signature of chaos in a quantum system is provided by spectral statistical analysis of the nearest-neighbor spacing distribution P(s) and the spectral rigidity given by the Delta(3)(L) statistic. It is shown that some standard unfolding[...]![]()
texto impreso
Pachón, Leonardo A. ; Relaño Pérez, Armando ; Peropadre, Borja ; Aspuru-Guzik, Alán | Amer Physical Soc | 2018-10-19Based on the connection between the spectral form factor and the probability to return, the origin of the energy level fluctuation 1/f(alpha) noise in fully chaotic and fully integrable systems is traced to the quantum interference between invar[...]![]()
texto impreso
Relaño Pérez, Armando ; Molina, R. A. ; Retamosa Granado, Joaquín ; Muñoz, L. ; Faleiro, E. ; Gómez Gómez, José María | IOP publishing ltd | 2010The power spectrum of the ?_(n) statistic of quantum spectra presents 1/ƒ^(?) noise. For chaotic systems ? = 1 while for regular systems ? = 2. Although the transition from regularity to chaos is non universal, for a wide variety of systems wi[...]![]()
texto impreso
Relaño Pérez, Armando ; Muñoz, L. ; Retamosa Granado, Joaquín ; Faleiro, E. ; Molina, R. A. | American Physical Society | 2008-03The continuous Gaussian ensemble, also known as the nu-Gaussian or nu-Hermite ensemble, is a natural extension of the classical Gaussian ensembles of real (nu= 1), complex (nu= 2), or quaternion (nu=4) matrices, where nu is allowed to take any p[...]![]()
texto impreso
Relaño Pérez, Armando ; Molina, R. A. ; Retamosa Granado, Joaquín ; Muñoz, L. ; Faleiro, E. | Elsevier Science BV | 2007-01-04Sequences of energy levels in nuclei are often plagued with missing levels whose number and position are unknown. It is also quite usual that all the quantum numbers of certain levels cannot be experimentally determined, and thus levels of diffe[...]![]()
texto impreso
Faleiro, E. ; Gómez Gómez, José María ; Muñoz, L. ; Relaño Pérez, Armando ; Retamosa Granado, Joaquín | University Chicago Press | 2004-11We apply a principal components analysis (PCA) to the secondary particle density distributions at ground level produced by cosmic gamma-rays and protons. For this purpose, high-energy interactions of cosmic rays with Earth's atmosphere and the r[...]![]()
texto impreso
Relaño Pérez, Armando ; Gómez Gómez, José María ; Molina, R. A. ; Retamosa Granado, Joaquín ; Faleiro, E. | American Physical Society | 2002-12-09The main signature of chaos in a quantum system is provided by spectral statistical analysis of the nearest-neighbor spacing distribution P(s) and the spectral rigidity given by the Delta(3)(L) statistic. It is shown that some standard unfolding[...]![]()
texto impreso
Puebla, Ricardo ; Relaño Pérez, Armando ; Retamosa Granado, Joaquín | American Institute of Physics (AIP) | 2013A method to find the Excited-States Quantum Phase Transitions (ESQPT's) from parity-symmetry in the Dicke model is studied and presented. This method allows us to stablish a critical energy where ESQPT's take places, and divides the whole energy[...]![]()
texto impreso
Relaño Pérez, Armando ; Dukelsky, J. ; Pérez Fernández, P. ; Arias, J. M. | American Physical Society | 2014-10-27The ground state and spectral properties of Bose gases in double-well potentials are studied in two different scenarios: (i) an interacting atomic Bose gas, and (ii) a mixture of an atomic gas interacting with diatomic molecules. A ground state [...]![]()
texto impreso
Pérez Fernández, P. ; Cejnar, P. ; Arias, J. M. ; Dukelsky, J. ; García Ramos, J. E. ; Relaño Pérez, Armando | American Physical Society | 2011-03-03We analyze excited-state quantum phase transitions (ESQPTs) in three schematic (integrable and nonintegrable) models describing a single-mode bosonic field coupled to a collection of atoms. It is shown that the presence of the ESQPT in these mod[...]![]()
texto impreso
Khatami, Ehsan ; Rigol, Marcos ; Relaño Pérez, Armando ; García García, Antonio M. | American Physical Society | 2012-05-15We study spectral properties and the dynamics after a quench of one-dimensional spinless fermions with short-range interactions and long-range random hopping. We show that a sufficiently fast decay of the hopping term promotes localization effec[...]![]()
texto impreso
Relaño Pérez, Armando ; Gómez Gómez, José María ; Faleiro, E. ; Muñoz, L. ; Molina, R. A. ; Retamosa Granado, J. | IOP publishing ltd | 2011A survey of chaotic dynamics in atomic nuclei is presented, using on the one hand standard statistics of quantum chaos studies, and on the other a new approach based on time series analysis methods. The study of shell-model spectra in the pf she[...]![]()
texto impreso
Gómez Gómez, José María ; Faleiro, E. ; Muñoz, L. ; Molina, R. A. ; Relaño Pérez, Armando | IOP publishing ltd | 2015Shell-model calculations with realistic empirical interactions constitute an excellent tool to study statistical properties of nuclei. Using large-scale shell-model calculations in pf-shell nuclei, we study how the onset of chaos depends on diff[...]![]()
texto impreso
We study the low-lying baryon spectrum (up to 2.2 GeV) provided by experiments and different quark models using statistical tools which allow us to postulate the existence of missing levels in spectra. We confirm that the experimental spectrum i[...]![]()
texto impreso
Relaño Pérez, Armando ; Muñoz, L. ; Faleiro, E. ; Molina, R. A. ; Retamosa Granado, Joaquín | American Physical Society | 2006-03It is widely accepted that the statistical properties of energy level spectra provide an essential characterization of quantum chaos. Indeed, the spectral fluctuations of many different systems like quantum billiards, atoms, or atomic nuclei hav[...]![]()
texto impreso
Relaño Pérez, Armando ; Molina, R. A. ; Zuker, A. P. ; Retamosa Granado, Joaquín | American Physical Society | 2005-06When a matrix is reduced to Lanczos tridiagonal form, its matrix elements can be divided into an analytic smooth mean value and a fluctuating part. The next-neighbor spacing distribution P(s) and the spectral rigidity Delta _(3) are shown to be [...]![]()
texto impreso
We compare the statistical fluctuation properties of the baryon and meson experimental mass spectra with those obtained from theoretical models (quark models and lattice QCD). We find that for the experimental spectra the statistical properties [...]![]()
texto impreso
Muñoz, Laura ; Fernández Ramírez, César ; Relaño Pérez, Armando ; Retamosa Granado, Joaquín | Elsevier Science BV | 2012-03-29We present a robust analysis of the spectral fluctuations exhibited by the light meson spectrum. This analysis provides information about the degree of chaos in light mesons and may be useful to get some insight on the underlying interactions. O[...]![]()
texto impreso
Relaño Pérez, Armando ; Dukelsky, J. ; Gómez Gómez, José María ; Retamosa Granado, Joaquín | American Physical Society | 2004-08Using a class of exactly solvable models based on the pairing interaction, we show that it is possible to construct integrable Hamiltonians with a Wigner distribution of nearest-neighbor level spacings. However, these Hamiltonians involve many-b[...]![]()
texto impreso
Relaño Pérez, Armando ; Faleiro, E. ; Gómez Gómez, José María ; Molina, R. A. ; Muñoz, L. ; Retamosa Granado, Joaquín | American Physical Society | 2004-12-10It was recently conjectured that 1/ƒ noise is a fundamental characteristic of spectral fluctuations in chaotic quantum systems. This conjecture is based on the power spectrum behavior of the excitation energy fluctuations, which is different for[...]![]()
texto impreso
Kota, V. K. B. ; Relaño Pérez, Armando ; Retamosa Granado, Joaquín ; Vyas, Manan | IOP Publishing | 2008-10-01Using the ergodicity principle for the expectation values of several types of observables, we investigate the thermalization process in isolated fermionic systems. These are described by the two-body random ensemble, which is a paradigmatic mode[...]![]()
texto impreso
Corps, Angel L. ; Molina, Rafael A. ; Relaño Pérez, Armando | American Physical Society | 2020-07-01We study the ergodic side of the many-body localization transition in its standard model, the disordered Heisenberg quantum spin chain. We show that the Thouless energy, extracted from long-range spectral statistics and the power-spectrum of the[...]