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We consider the possibility of quantum phase transitions in the ground state of triplet superconductors where particle density is the tunning parameter. For definiteness, we focus on the case of one band quasi-one-dimensional triplet…

Superconductivity · Physics 2016-08-16 R. W. Cherng , C. A. R. Sá de Melo

We consider the energy averaged two-point correlator of spectral determinants and calculate contributions beyond the diagonal approximation using semiclassical methods. Evaluating the contributions originating from pseudo-orbit correlations…

Chaotic Dynamics · Physics 2015-05-13 Daniel Waltner , Stefan Heusler , Juan Diego Urbina , Klaus Richter

We propose an approach to the study of open quantum systems based on a parametric representation of the principal system. The representation is obtained introducing generalized coherent states for the environment, and is such that the…

Quantum Physics · Physics 2013-12-12 Dario Calvani , Alessandro Cuccoli , Nikitas Gidopoulos , Paola Verrucchi

Geometric symmetries cause orbital degeneracies in a molecule's spectrum. In a single-molecule junction, these degeneracies are lifted by various symmetry-breaking effects. We study quantum transport through such nanostructures with an…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 Maximilian G. Schultz , Felix von Oppen

The S-matrix theory formulation of closed-orbit theory recently proposed by Granger and Greene is extended to atoms in crossed electric and magnetic fields. We then present a semiclassical quantization of the hydrogen atom in crossed…

Chaotic Dynamics · Physics 2009-11-07 T. Bartsch , J. Main , G. Wunner

In this article, we analyze the propagation of Wigner measures of a family of solutions to a system of semi-classical pseudodifferential equations presenting eigenvalues crossings on hypersurfaces. We prove the propagation along classical…

Mathematical Physics · Physics 2008-11-14 Thomas Duyckaerts , Clotilde Fermanian Kammerer , Thierry Jecko

We consider a quantum system constituted by $N$ identical particles interacting by means of a mean-field Hamiltonian. It is well known that, in the limit $N\to\infty$, the one-particle state obeys to the Hartree equation. Moreover,…

Mathematical Physics · Physics 2015-05-13 Federica Pezzotti , Mario Pulvirenti

We show the transition from a fully quantized interaction to a semiclassical one in entangled small number quantum systems using the quantum trajectories approach. In particular, we simulate the microwave Ramsey zones used in Rydberg atom…

Quantum Physics · Physics 2011-05-31 Eduardo Mascarenhas , Marcelo França Santos

We study the behavior of an open quantum system, with an $N$--dimensional space of states, whose density matrix evolves according to a non--unitary map defined in two steps: A unitary step, where the system evolves with an evolution…

Quantum Physics · Physics 2009-11-07 Pablo Bianucci , Juan Pablo Paz , Marcos Saraceno

Energy level statistics of quantized chaotic systems have been evaluated in the semiclassical limit via their periodic orbits using the Gutzwiller and related trace formulae. Here we evaluate a spectral statistic of chaotic 4-regular…

Quantum Physics · Physics 2022-05-25 Jon Harrison , Tori Hudgins

A formula to calculate the quantum fluctuations of energy in small subsystems of a hot and relativistic gas is derived. We find an increase in fluctuations for subsystems of small sizes, but we agrees with the energy fluctuations in the…

Nuclear Theory · Physics 2021-10-08 Rajeev Singh

Quantum mechanics has been formulated in phase space, with the Wigner function as the representative of the quantum density operator, and classical mechanics has been formulated in Hilbert space, with the Groenewold operator as the…

Quantum Physics · Physics 2017-02-23 A. J. Bracken , J. G. Wood

On the basis of extensive numerical studies it is argued that there are strong analogies between the probabilistic behavior of quantum systems defined by Hermitian Hamiltonians and the deterministic behavior of classical mechanical systems…

High Energy Physics - Theory · Physics 2010-05-28 Carl M. Bender , Dorje C. Brody , Daniel W. Hook

Starting from the Schr\"odinger-equation of a composite system, we derive unified dynamics of a classical harmonic system coupled to an arbitrary quantized system. The classical subsystem is described by random phase-space coordinates…

Quantum Physics · Physics 2007-05-23 Lajos Diosi

We investigate dynamics of semi-quantal spin systems in which quantum bits are attached to classically and possibly stochastically moving classical particles. The interaction between the quantum bits takes place when the respective…

Quantum Physics · Physics 2009-11-13 Matyas Koniorczyk , Arpad Varga , Peter Rapcan , Vladimir Buzek

A class of models is considered for a quantum particle constrained on degenerate Riemannian manifolds known as Grushin cylinders, and moving freely subject only to the underlying geometry: the corresponding spectral analysis is developed in…

Spectral Theory · Mathematics 2021-05-25 Matteo Gallone , Alessandro Michelangeli

This study explores the semiclassical limit of an integrable-chaotic bosonic many-body quantum system, providing nuanced insights into its behavior. We examine classical-quantum correspondences across different interaction regimes of bosons…

An analysis of the semiclassical regime of the quantum-classical transition is given for open, bounded, one dimensional chaotic dynamical systems. Environmental fluctuations -- characteristic of all realistic dynamical systems -- suppress…

Quantum Physics · Physics 2009-11-10 Benjamin D. Greenbaum , Salman Habib , Kosuke Shizume , Bala Sundaram

I investigate quantum decoherence in a one-body density matrix of a composite particle consisting of two correlated particles. Because of a two-body correlation in the composite particle, quantum decoherence occurs in the one-body density…

Quantum Physics · Physics 2016-06-21 Yoshiko Kanada-En'yo

Quantum chaos of many-body systems has been swiftly developing into a vibrant research area at the interface between various disciplines, ranging from statistical physics to condensed matter to quantum information and to cosmology. In…

Quantum Physics · Physics 2022-11-23 Klaus Richter , Juan Diego Urbina , Steven Tomsovic