English
Related papers

Related papers: Decoherence of Semiclassical Wigner Functions

200 papers

A semiclassical approximation for an evolving density operator, driven by a "closed" hamiltonian operator and "open" markovian Lindblad operators, is obtained. The theory is based on the chord function, i.e. the Fourier transform of the…

Quantum Physics · Physics 2020-08-18 A. M. Ozorio de Almeida , P. de M. Rios , O. Brodier

The exact solution of the Lindblad equation with a quadratic Hamiltonian and linear coupling operators was derived within the chord representation, that is, for the Fourier transform of the Wigner function, also known as the characteristic…

Quantum Physics · Physics 2023-10-04 Aldo R. Fernandes Neto , Alfredo M. Ozorio de Almeida , Olivier Brodier

The time evolution of the Wigner function for Gaussian states generated by Lindblad quantum dynamics is investigated in the semiclassical limit. A new type of phase-space dynamics is obtained for the centre of a Gaussian Wigner function,…

Quantum Physics · Physics 2019-02-01 E M Graefe , B Longstaff , T Plastow , R Schubert

Classical surfaces in phase space correspond to quantum states in Hilbert space. Subsystems specify factor spaces of the Hilbert space. An entangled state corresponds semiclassically to a surface that cannot be decomposed into a product of…

Quantum Physics · Physics 2007-05-23 A. M. Ozorio de Almeida

The Heisenberg evolution of a given unitary operator corresponds classically to a fixed canonical transformation that is viewed through a moving coordinate system. The operators that form the bases of the Weyl representation and its Fourier…

Quantum Physics · Physics 2007-05-23 A. M. Ozorio de Almeida , O. Brodier

The damping of the harmonic oscillator is studied in the framework of the Lindblad theory for open quantum systems. A generalization of the fundamental constraints on quantum mechanical diffusion coefficients which appear in the master…

Quantum Physics · Physics 2015-06-26 A. Isar , A. Sandulescu , H. Scutaru , E. Stefanescu , W. Scheid

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

We derive a semiclassical approximation for the evolution generated by the Lindblad equation as a generalization of complex WKB theory. Linear coupling to the environment is assumed, but the Hamiltonian can be a general function of…

Quantum Physics · Physics 2015-05-13 O. Brodier , A. M. Ozorio de Almeida

The trace of an arbitrary product of quantum operators with the density operator is rendered as a multiple phase space integral of the product of their Weyl symbols with the Wigner function. Interspersing the factors with various evolution…

Quantum Physics · Physics 2016-04-20 Alfredo M. Ozorio de Almeida , Olivier Brodier

We derive an approximate Gaussian solution of the Lindblad equation in the semiclassical limit, given a general Hamiltonian and linear coupling with the environment. The theory is carried out in the chord representation and describes the…

Quantum Physics · Physics 2009-06-24 O. Brodier , A. M. Ozorio de Almeida

The Weyl-Wigner representation of quantum mechanics allows one to map the density operator in a function in phase space - the Wigner function - which acts like a probability distribution. In the context of statistical mechanics, this…

Quantum Physics · Physics 2023-08-31 Marcos Gil de Oliveira , Alfredo Miguel Ozorio de Almeida

The harmonic oscillator with dissipation is studied within the framework of the Lindblad theory for open quantum systems. By using the Wang-Uhlenbeck method, the Fokker-Planck equation, obtained from the master equation for the density…

High Energy Physics - Theory · Physics 2007-05-23 Aurelian Isar

In this work we study the Wigner functions, which are the quantum analogues of the classical phase space density, and show how a full rigorous semiclassical scheme for all orders of \hbar can be constructed for them without referring to the…

Chaotic Dynamics · Physics 2009-11-07 Gregor Veble , Marko Robnik , Valery Romanovski

Time evolution of the expectation values of various dynamical operators of the harmonic oscillator with dissipation is analitically obtained within the framework of the Lindblad's theory for open quantum systems. We deduce the density…

High Energy Physics - Theory · Physics 2007-05-23 Aurelian Isar

We present a Wigner function-based approach for the particle density evolution in fermionic and bosonic open quantum many-body systems, including the effects of dephasing. In particular, we focus on chains of non-interacting particles…

Quantum Gases · Physics 2023-05-31 Michele Coppola , Gabriel T. Landi , Dragi Karevski

A closed expression for the density operator of the damped harmonic oscillator is extracted from the master equation based on the Lindblad theory for open quantum systems. The entropy and effective temperature of the system are subsequently…

High Energy Physics - Theory · Physics 2007-05-23 A. Isar

Time evolution of the expectation values of various dynamical operators of the harmonic oscillator with dissipation is analitically obtained within the framework of the Lindblad theory for open quantum systems. We deduce the density matrix…

Quantum Physics · Physics 2007-05-23 A. Isar

The Wigner function is known to evolve classically under the exclusive action of a quadratic hamiltonian. If the system does interact with the environment through Lindblad operators that are linear functions of position and momentum, we…

Quantum Physics · Physics 2009-11-10 O. Brodier , A. M. Ozorio de Almeida

The expression for the density operator of the damped harmonic oscillator is derived from the master equation in the framework of the Lindblad theory for open quantum systems. Then the von Neumann entropy and effective temperature of the…

Quantum Physics · Physics 2007-05-23 A. Isar

In the framework of the Lindblad theory for open quantum systems the damping of the harmonic oscillator is studied. A generalization of the fundamental constraints on quantum mechanical diffusion coefficients which appear in the master…

Quantum Physics · Physics 2007-05-23 A. Isar , A. Sandulescu
‹ Prev 1 2 3 10 Next ›