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Continuous phase-space methods on discrete phase spaces
(EPL Association, 2015)
We show that discrete quasiprobability distributions defined via the discrete
Heisenberg-Weyl group can be obtained as discretizations of the continuous SU(N) quasiprobability
distributions. This is done by identifying ...
Optimal quantum control applied to quantum dots
(Universidade Federal de São CarlosUFSCarPrograma de Pós-Graduação em Física - PPGFCâmpus São Carlos, 2019-10-03)
In the present study, we review the one-qubit dynamics and we offer a new unifying interpretation of the Landau-Zenner and the Rabi dynamics, by indicating the physical elements responsible for the manifestation of one ...
Inhomogeneous Fermi and quantum spin systems on lattices
(AMER INST PHYSICSMELVILLE, 2012)
We study the thermodynamic properties of a certain type of space-inhomogeneous Fermi and quantum spin systems on lattices. We are particularly interested in the case where the space scale of the inhomogeneities stays ...
Determination of heisenberg exchange coupling constants in clusters with magnetic sites: A local spin approach
(John Wiley & Sons Inc, 2014-04)
This work studies the ability of the two-center local spin quantities, provided by the partitioning of the expectation value of the spin-squared operator math formula corresponding to N-electron systems, for determining ...
Decoherent time-dependent transport beyond the Landauer-Büttiker formulation: A quantum-drift alternative to quantum jumps
(American Physical Society, 2015-02)
We develop and implement a model for decoherence in time-dependent transport. Inspired in a dynamical formulation of the Landauer-Büttiker equations, it boils down into a form of wave function that undergoes a smooth ...
Impurity effects in the quantum kagome system Zn Cu3 (OH)6 Cl2
(American Physical Society, 2008-12)
Motivated by the recent experiments on the spin half kagome compound Zn Cu3 (OH)6 Cl2, we study a phenomenological model of a frustrated quantum magnet. The model has a spin liquid ground state and is constructed so as to ...
Spin-polarized current and shot noise in the presence of spin flip in a quantum dot via nonequilibrium Green's functions
(AMER PHYSICAL SOC, 2008)
Using nonequilibrium Green's functions we calculate the spin-polarized current and shot noise in a ferromagnet-quantum-dot-ferromagnet system. Both parallel (P) and antiparallel (AP) magnetic configurations are considered. ...