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Properties of the geometric phase for a nonstatic coherent light-wave arisen in a static environment are analyzed from various angles. The geometric phase varies in a regular nonlinear way, where the center of its variation increases…

Quantum Physics · Physics 2024-03-19 Jeong Ryeol Choi

We consider the generalized pure state density matrix which depends on different time moments. The evolution equation for this density matrix is obtained in case where the density matrix corresponds to the solutions of Gross-Pitaevskii…

Quantum Physics · Physics 2019-02-12 V. N. Chernega , O. V. Man'ko , V. I. Man'ko

In the framework of the Lindblad theory for open quantum systems, expressions for the density operator, von Neumann entropy and effective temperature of the damped harmonic oscillator are obtained. The entropy for a state characterized by a…

Quantum Physics · Physics 2015-06-26 A. Isar

The nonequilibrium dynamics in chaotic quantum systems denies a fully understanding up to now, even if thermalization in the long-time asymptotic state has been explained by the eigenstate thermalization hypothesis which assumes a universal…

Statistical Mechanics · Physics 2020-12-08 Xinxin Yang , Pei Wang

In the following, we study the dissipative time-evolution of a quantum chain consisting of three coupled harmonic oscillators, the first and third of which weakly interact quadratically with two independent thermal baths in equilibrium at…

Quantum Physics · Physics 2025-05-23 Melika Babakan , Fabio Benatti , Laleh Memarzadeh

We study the stability of unitary quantum dynamics of composite systems (for example: central system + environment) with respect to weak interaction between the two parts. Unified theoretical formalism is applied to study different physical…

Quantum Physics · Physics 2009-11-07 Marko Znidaric , Tomaz Prosen

Quantum dynamics of a damped harmonic oscillator has been extensively studied since the sixties of the last century. Here, with a distinct tool termed the ``group-theoretical characteristic function" (GCF), we investigate analytically how a…

Quantum Physics · Physics 2025-10-01 Yan Gu , Jiao Wang

Using a density matrix description in space we study the evolution of wavepackets in a fluctuating space-time background. We assume that space-time fluctuations manifest as classical fluctuations of the metric. From the non-relativistic…

General Relativity and Quantum Cosmology · Physics 2010-04-30 E. Göklü , C. Lämmerzahl , A. Camacho , A. Macias

The time evolution of a qubit, consisting of two single-level quantum dots, is studied in the presence of telegraph noise. The dots are connected by two tunneling paths, with an Aharonov-Bohm flux enclosed between them. Under special…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 A. Aharony , S. Gurvitz , O. Entin-Wohlman , S. Dattagupta

Exact solutions of the Caldeira-Leggett Master equation for the reduced density matrix for a free particle and for a harmonic oscillator system coupled to a heat bath of oscillators are obtained for arbitrary initial conditions. The…

Quantum Physics · Physics 2007-05-23 S. M. Roy , Anu Venugopalan

First, we have generalized the notion of Franhoufer diffraction of temporal coherent light from a single slit to the case of arbitrary n-slits. The diffraction pattern is investigated for different values of recently [19] introduced…

Optics · Physics 2023-10-20 E. Koushki , S. A. Alavi

It is shown that if the decoherence matrix corresponding to a qubit master equation has a block-diagonal real part, then the evolution is determined by a one-dimensional oscillator equation. Further, when the full decoherence matrix is…

Quantum Physics · Physics 2009-11-13 Michael J. W. Hall

We consider the evolution of a quantum simple harmonic oscillator in a general Gaussian state under simultaneous time-continuous weak position and momentum measurements. We deduce the stochastic evolution equations for position and momentum…

Quantum Physics · Physics 2022-03-16 Tathagata Karmakar , Philippe Lewalle , Andrew N. Jordan

We study various temporal correlation functions of a tagged particle in one-dimensional systems of interacting point particles evolving with Hamiltonian dynamics. Initial conditions of the particles are chosen from the canonical thermal…

Statistical Mechanics · Physics 2015-06-25 Anjan Roy , Abhishek Dhar , Onuttom Narayan , Sanjib Sabhapandit

Evolution of coherent states is considered for a particle confined to a cylinder moving in a harmonic oscillator potential. Because of the discontinuous changes as time goes by of the phase representing the position of a particle on a…

Quantum Physics · Physics 2013-08-14 K. Kowalski , J. Rembieliński

When a quantum system is quenched from its ground state, the time evolution can lead to non-analytic behavior in the return rate at critical times $t_c$. Such dynamical phase transitions (DPT's) can occur, in particular, for quenches…

Statistical Mechanics · Physics 2018-02-07 N. Sedlmayr , M. Fleischhauer , J. Sirker

We analyze the time evolution describing a quantum source for noninteracting particles, either bosons or fermions. The growth behaviour of the particle number (trace of the density matrix) is investigated, leading to spectral criteria for…

Mathematical Physics · Physics 2015-05-14 Maximilian Butz , Herbert Spohn

The initial-boundary value problem for an infinite one-dimensional chain of harmonic oscillators on the half-line is considered. The large time asymptotic behavior of solutions is studied. The initial data of the system are supposed to be a…

Mathematical Physics · Physics 2018-07-24 T. V. Dudnikova

We characterize the early stages of the approach to equilibrium in isolated quantum systems through the evolution of the entanglement spectrum. We find that the entanglement spectrum of a subsystem evolves with at least three distinct…

Disordered Systems and Neural Networks · Physics 2019-11-12 Po-Yao Chang , Xiao Chen , Sarang Gopalakrishnan , J. H. Pixley

We examine an extension to the theory of Gaussian wave packet dynamics in a one-dimensional potential by means of a sequence of time dependent displacement and squeezing transformations. Exact expressions for the quantum dynamics are found,…

Atomic Physics · Physics 2009-10-31 B. M. Garraway