English
Related papers

Related papers: Density operator and entropy of the damped quantum…

200 papers

The thermodynamic entropy of an isolated system is given by its von Neumann entropy. Over the last few years, there is an intense activity to understand thermodynamic entropy from the principles of quantum mechanics. More specifically, is…

Quantum Physics · Physics 2016-07-19 S. Santhosh Kumar , S. Shankaranarayanan

In this manuscript we study the Wehrl entropy of entangled oscillators. This semiclassical entropy associated with the phase-space description of quantum mechanics can be used for formulating uncertainty relations and for a quantification…

The quadrature distribution for the quantum damped oscillator is introduced in the framework of the formulation of quantum mechanics based on the tomography scheme. The probability distribution for the coherent and Fock states of the damped…

Quantum Physics · Physics 2011-04-15 S. S. Safonov

In this work we study the behaviour of two weakly coupled quantum systems, described by a separable density operator; one of them is a single oscillator, representing a microscopic system, while the other is a set of oscillators which…

Mathematical Physics · Physics 2016-08-24 Jeferson Tomazelli , Renan Cunha

Control of open quantum dynamics is of great interest for realizing quantum technologies. Therefore, it is an important task to quantify and characterize the entropy for open quantum systems under decoherence. In this paper, we study the…

Quantum Physics · Physics 2024-05-21 Kohei Kobayashi

Some aspects of quantum damped harmonic oscillator (DHO) obeying a Markovian master equation are considered in the absence of thermal noise. The continuity equation is derived and Bohmian trajectories are constructed. As a solution of the…

Quantum Physics · Physics 2023-05-18 S. V. Mousavi

We consider ensembles of bipartite states resulting from a random passive Gaussian unitary applied to a fiducial pure Gaussian state. We show that the symplectic spectra of the reduced density operators concentrate around that of a thermal…

Quantum Physics · Physics 2019-12-02 Motohisa Fukuda , Robert Koenig

We present a new proposal for distinguishing heat from work based on a control-theoretic observability decomposition. We derive a Hermitian operator representing instantaneous dissipation of observable energy, and suggest a generalization…

Quantum Physics · Physics 2024-03-28 William Rupush , Oscar Grånäs

We study the entropy of small subsystems in thermalizing quantum many-body systems governed by local Hamiltonians. Assuming the eigenstate thermalization hypothesis, we derive an analytical formula for the von Neumann entropy of…

Statistical Mechanics · Physics 2025-02-03 Yichen Huang

The change of the von Neumann entropy of a set of harmonic oscillators initially in thermal equilibrium and interacting linearly with an externally driven quantum system is computed by adapting the Feynman-Vernon influence functional…

Statistical Mechanics · Physics 2018-04-04 Erik Aurell , Ralf Eichhorn

The effect of a thermal reservoir is investigated on a bipartite Gaussian state. We derive a pre-Lindblad master equation in the non-rotating wave approximation for the system. We then solve the master equation for a bipartite harmonic…

Quantum Physics · Physics 2010-08-19 Anne Ghesquière , Tony C. Dorlas

We show theoretically how a driven harmonic oscillator can be used as a quantum simulator for non-Markovian damped harmonic oscillator. In the general framework, the results demonstrate the possibility to use a closed system as a simulator…

Quantum Physics · Physics 2009-11-13 Jyrki Piilo , Sabrina Maniscalco

Simulations are performed of a small quantum system interacting with a quantum environment. The system consists of various initial states of two harmonic oscillators coupled to give normal modes. The environment is "designed" by its level…

Statistical Mechanics · Physics 2015-06-15 George L. Barnes , Michael E. Kellman

We generalized the squeeze and displacement operators of the one-dimensional harmonic oscillator to the three-dimensional case and based on these operators we construct the corresponding coherent and squeezed states. We have also calculated…

Quantum Physics · Physics 2011-05-17 Mehdi Miri , Sina Khorasani

We reanalyse the quantum damped harmonic oscillator, introducing three less than common features. These are (i) the use of a continuum model of the reservoir rather than an ensemble of discrete oscillators, (ii) an exact diagonalisation of…

Quantum Physics · Physics 2023-06-28 Stephen M. Barnett , James D. Cresser , Sarah Croke

The work is devoted to the study of quantum integrable systems associated with quantum loop algebras. The recently obtained equation for the zero temperature inhomogeneous reduced density operator is analyzed. It is demonstrated that any…

Mathematical Physics · Physics 2020-04-07 Alexander V. Razumov

As an application of the classically decayable correlation in a quantum chaos system maintained over an extremely long time-scale (Matsui et al, Europhys.Lett. 113(2016),40008), we propose a minimal model of quantum damper composed of a…

Statistical Mechanics · Physics 2018-07-20 Fumihiro Matsui , Hiroaki S. Yamada , Kensuke S. Ikeda

The probability operator is derived from first principles for an equilibrium quantum system. It is also shown that the superposition states collapse into a mixture of states giving the conventional von Neumann trace form for the quantum…

Statistical Mechanics · Physics 2014-01-09 Phil Attard

The time development of the reduced density matrix for a quantum oscillator damped by coupling it to an ohmic environment is calculated via an identity of the Debye-Waller form. Results obtained some years ago by Hakim and the author in the…

Quantum Physics · Physics 2015-06-26 Vinay Ambegaokar

The Von Neumann entropy of reduced states is a measure of bipartite entanglement. Despite its name, the entanglement entropy cannot by itself be used as a resource for creating thermodynamic heat flows. In order to extract heat from an…

Quantum Physics · Physics 2026-05-04 Lisa Lenstra , Jasper van Wezel