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Related papers: Exact Density matrix of an oscillator-bath system:…

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An exact method to compute the entire equilibrium reduced density matrix for systems characterized by a system-bath Hamiltonian is presented. The approach is based upon a stochastic unraveling of the influence functional that appears in the…

Mesoscale and Nanoscale Physics · Physics 2015-06-04 Jeremy M. Moix , Yang Zhao , Jianshu Cao

Using the path integral representation of the density matrix propagator of quantum Brownian motion, we derive its asymptotic form for times greater than the localization time, $ (\hbar / \gamma k T )^{\half}$, where $\gamma$ is the…

Quantum Physics · Physics 2008-12-18 Jonathan Halliwell , Andreas Zoupas

We derive the exact out-of-equilibrium Wigner function of a bosonic mode linearly coupled to a bosonic bath of arbitrary spectral density. Our solution does not rely on any master equation approach and it therefore also correctly describes…

Quantum Physics · Physics 2014-01-13 A. Rancon , J. Bonart

We employ the influence functional technique to trace out the photonic contribution from full quantum electrodynamics. The reduced density matrix propagator for the spinor field is then constructed. We discuss the role of time-dependent…

High Energy Physics - Theory · Physics 2009-10-30 C. Anastopoulos , A. Zoupas

In this paper we solve for the quantum propagator of a general time dependent system quadratic in both position and momentum, linearly coupled to an infinite bath of harmonic oscillators. We work in the regime where the quantum optical…

General Relativity and Quantum Cosmology · Physics 2008-11-26 J. Twamley

We formulate exact generalized nonequilibrium fluctuation relations for the quantum mechanical harmonic oscillator coupled to multiple harmonic baths. Each of the different baths is prepared in its own individual (in general nonthermal)…

Quantum Physics · Physics 2015-06-17 D. Pagel , P. Nalbach , A. Alvermann , H. Fehske , M. Thorwart

We calculate the reduced density matrix for a system of coupled harmonic oscillators in a bosonic heat bath using the Born-Markov approximation and show that the expectation values of position and momentum evolve like classical quantities.…

Statistical Mechanics · Physics 2011-08-09 Björn Bartels

We consider a molecular aggregate consisting of $N$ identical monomers. Each monomer comprises two electronic levels and a single harmonic mode. The monomers interact with each other via dipole-dipole forces. The monomer vibrational modes…

Statistical Mechanics · Physics 2012-04-12 Maxim F. Gelin , Dassia Egorova , Wolfgang Domcke

The study of quantum thermodynamics is key to the development of quantum thermal machines. In contrast to most of the previous proposals based on discrete strokes, here we consider a working substance that is permanently coupled to two or…

Quantum Physics · Physics 2022-02-09 Heather Leitch , Nicolò Piccione , Bruno Bellomo , Gabriele De Chiara

A master equation for the deformed quantum harmonic oscillator interacting with a dissipative environment, in particular with a thermal bath, is derived in the microscopic model by using perturbation theory, for the case when the…

Quantum Physics · Physics 2009-11-13 A. Isar , W. Scheid

An explicit demonstration is given of a harmonic oscillator in equilibrium approaching the equilibrium of a corresponding interacting system by coupling it to a thermal bath consisting of a continuum of harmonic oscillators.

Quantum Physics · Physics 2007-06-27 Vinay Ambegaokar

The problem of quantum harmonic oscillator with "regular+random" square frequency, subjected to "regular+random external force, is considered in framework of representation of the wave function by complex-valued random process. Average…

Quantum Physics · Physics 2007-05-23 A. S. Gevorkyan , A. A. Udalov

We derive an exact quantum propagator for nonadiabatic dynamics in multi-state systems using the mapping variable representation, where classical-like Cartesian variables are used to represent both continuous nuclear degrees of freedom and…

Chemical Physics · Physics 2017-07-25 Timothy J. H. Hele , Nandini Ananth

In this paper we present a new quantum-trajectory based treatment of quantum dynamics suitable for dissipative systems. Starting from a de Broglie/Bohm-like representation of the quantum density matrix, we derive and define quantum…

Quantum Physics · Physics 2007-05-23 Jeremy B. Maddox , Eric R. Bittner

We derive the exact time-evolution for a general quantum system under the influence of pure phase-noise and demonstrate that for a Gaussian initial state of the bath, the exact result can be obtained also within a perturbative time-local…

Quantum Physics · Physics 2008-05-13 Roland Doll , David Zueco , Martijn Wubs , Sigmund Kohler , Peter Hanggi

A generalization of driven harmonic oscillator with time-dependent mass and frequency, by adding total time-derivative terms to the Lagrangian, is considered. The generalization which gives a general quadratic Hamiltonian system does not…

Quantum Physics · Physics 2009-10-31 Dae-Yup Song

Using linear invariant operators in a constructive way we find the most general thermal density operator and Wigner function for time-dependent generalized oscillators. The general Wigner function has five free parameters and describes the…

Quantum Physics · Physics 2007-05-23 Sang Pyo Kim , Don N. Page

The dissipative quantum electromagnetics is introduced in a comprehensive manner as a field-matter-bath coupling problem. First, the matter is described by a cluster of Lorentz oscillators. Then the Maxwellian free field is coupled to the…

Quantum Physics · Physics 2018-11-21 Wei E. I. Sha , Aiyin Y. Liu , Weng Cho Chew

We consider a qubit coupled to a nonlinear quantum oscillator, the latter coupled to an Ohmic bath, and investigate the qubit dynamics. This composed system can be mapped onto that of a qubit coupled to an effective bath. An approximate…

Quantum Physics · Physics 2015-05-20 Carmen Vierheilig , Dario Bercioux , Milena Grifoni

A master equation for the deformed quantum harmonic oscillator interacting with a dissipative environment, in particular with a thermal bath, is derived in the microscopic model by using perturbation theory. The coefficients of the master…

Quantum Physics · Physics 2009-11-13 A. Isar , W. Scheid