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Artículo
An extended Agassi model: Algebraic structure, phase diagram, and large size limit
(Institute of Physics Publishing, 2019)
The Agassi model (Agassi 1968 Nucl. Phys. A 116 49) is a schematic two-level model that involves pairing and monopole-monopole interactions. It is, therefore, an extension of the well known Lipkin-Meshkov-Glick model (Lipkin ...
Artículo
Excited-state phase transition and onset of chaos in quantum optical models
(American Physical Society, 2011)
We study the critical behavior of excited states and its relation to order and chaos in the Jaynes-Cummings and Dicke models of quantum optics. We show that both models exhibit a chain of excited-state quantum phase ...
Artículo
One-particle spectroscopic intensities as a signature of shape phase transition: The γ -unstable case
(American Physical Society, 2006-08-09)
We investigate the evolution of one-particle spectroscopic intensities as a possible signature of shape phase transitions. The study describes the odd systems in terms of the interacting boson–fermion model. We consider ...
Ponencia
Quantum phase transitions in odd-A nuclei: The effect of the odd particle from spherical to oblate shapes
(Institute of Physics Publishing, 2015)
Quantum shape-phase transitions in odd-nuclei are investigated within the framework of the interacting boson-fermion model (IBFM). We consider the case of a single-j fermion coupled to an even-even boson core that performs ...
Artículo
Number conserving particle-hole RPA for superfluid nuclei
(Elsevier, 2019-08)
We present a number conserving particle-hole RPA theory for collective excitations in the transition from normal to superfluid nuclei. The method derives from an RPA theory developed long ago in quantum chemistry using ...
Ponencia
Probing 6He structure from proton inelastic collisions
(American Institute of Physics, 2006)
We explore the Hyperspherical Harmonics pseudostate method to describe the 6He continuum. The method is use it within the multiple scattering of the transition amplitude (MST) approach to study inelastic scattering of p-6He ...
Artículo
Quantum phase transitions in the interacting boson model: Integrability, level repulsion, and level crossing
(American Physical Review, 2003-10-17)
We study the quantum phase transition mechanisms that arise in the interacting boson model. We show that the second-order nature of the phase transition from U(5) to O(6) may be attributed to quantum integrability, whereas ...
Artículo
Decoherence due to an excited-state quantum phase transition in a two-level boson model
(American Physical Society, 2009)
The decoherence induced on a single qubit by its interaction with the environment is studied. The environment is modeled as a scalar two-level boson system that can go through either first-order or continuous-excited-state ...
Tesis Doctoral
Desarrollos microscópicos y cálculos en el marco del modelo de bosones y fermiones en interacción
(2002-12-10)
La presente Tesis Doctoral se desarrolla en el marco de los modelos de bosones en interacción (IBM) y de bosones y fermiones en interacción (IBFM), los cuales permiten estudiar las propiedades de los estados colectivos más ...
Artículo
β4 potential at the U(5)–O(6) critical point of the interacting boson model
(American Physical Society, 2005)
Exact numerical results of the interacting boson model Hamiltonian along the integrable line from U(5) to O(6) are obtained by diagonalization within boson seniority subspaces. The matrix Hamiltonian reduces to a block ...