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Strong-disorder renormalization-group study of the one-dimensional tight-binding model
(American Physical Society - APSCollege Park, 2014-09)
We formulate a strong-disorder renormalization-group (SDRG) approach to study the β function of the tight-binding model in one dimension with both diagonal and off-diagonal disorder for states at the band center. We show ...
Quadrupolar analogous for nematic phaseAnálogo quadrupolar para a Fase Nemática
(Universidade Federal de Santa Maria, 1991)
Transicões inversas em modelos fermiônicos de vidro de spin
(Universidade Federal de Santa MariaBRFísicaUFSMPrograma de Pós-Graduação em Física, 2010-08-26)
The present work studies inverse transitions by using two spin glass models: the infinite-range fermionic Ising spin glass (FISG) in the presence of a transverse magnetic field
¡ and Hopfield fermionic Ising spin glass ...
Orbital multicriticality in spin-gapped quasi-one-dimensional antiferromagnets
(AMER PHYSICAL SOC, 2011)
Motivated by the quasi-one-dimensional antiferromagnet CaV(2)O(4), we explore spin-orbital systems in which the spin modes are gapped but orbitals are near a macroscopically degenerate classical transition. Within a ...
Estudo da transição de fase de 1ª ordem no KH2PO4
(Universidade Federal de Minas GeraisUFMG, 1977-03-01)
Recent experimental data show that the KDP phase transition is of the first order. The well Known model hamiltonian for KDP, na Ising interaction on a transverse field for pseudo-spins operators, produces a second order ...
Operational classification and quantification of multipartite entangled states
(American Physical SocCollege PkEUA, 2006)
Rounding of a first-order quantum phase transition to a strong-coupling critical point
(AMER PHYSICAL SOCCOLLEGE PK, 2012)
We investigate the effects of quenched disorder on first-order quantum phase transitions on the example of the N-color quantum Ashkin-Teller model. By means of a strong-disorder renormalization group, we demonstrate that ...
Congelamento inverso em um modelo de vidro de spin com Clusters
(Universidade Federal de Santa MariaBRFísicaUFSMPrograma de Pós-Graduação em Física, 2014-08-29)
This work analyzes a spin glass (SG) model with cluster in two versions: a classic version with Ising spins and in a fermionic version with spin operators. In this model,
the basic entities are correlated clusters that ...
Universal behavior of the Shannon and Rényi mutual information of quantum critical chains
(American Physical Society - APSCollege Park, 2014-08)
We study the Shannon and Rényi mutual information (MI) in the ground state (GS) of different critical quantum spin chains. Despite the apparent basis dependence of these quantities we show the existence of some particular ...