English
Related papers

Related papers: Coherent States Expectation Values as Semiclassica…

200 papers

The decoherence of quantum states defines the transition between the quantum world and classical physics. Decoherence or, analogously, quantum mechanical collapse events pose fundamental questions regarding the interpretation of quantum…

Mesoscale and Nanoscale Physics · Physics 2021-09-24 P. Bredol , H. Boschker , D. Braak , J. Mannhart

We provide an introduction to deformation quantisation and discuss the application of the formalism in solving the evolution problem for many-body systems in terms of semiclassical expansion. In any fixed order of expansion over the…

Nuclear Theory · Physics 2012-07-03 M. I. Krivoruchenko

Electronic transport through chaotic quantum dots exhibits universal, system independent, properties, consistent with random matrix theory. The quantum transport can also be rooted, via the semiclassical approximation, in sums over the…

Chaotic Dynamics · Physics 2013-03-06 Gregory Berkolaiko , Jack Kuipers

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 calculate the power spectrum of density fluctuations in the statistical non-equilibrium field theory for classical, microscopic degrees of freedom to first order in the interaction potential. We specialise our result to cosmology by…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-07 Matthias Bartelmann , Felix Fabis , Daniel Berg , Elena Kozlikin , Robert Lilow , Celia Viermann

The complex geometry underlying the Schr\"odinger dynamics of coherent states for non-Hermitian Hamiltonians is investigated. In particular two seemingly contradictory approaches are compared: (i) a complex WKB formalism, for which the…

Mathematical Physics · Physics 2012-07-12 Eva-Maria Graefe , Roman Schubert

Under certain conditions, the quantum delta-kicked harmonic oscillator displays quantum resonances. We consider an atom-optical realization of the delta-kicked harmonic oscillator, and present a theoretical discussion of the quantum…

Quantum Physics · Physics 2010-08-03 T. P. Billam , S. A. Gardiner

Quantum phase transitions and observables of interest of the ground state in the Tavis-Cummings model are analyzed, for any number of atoms, by using a tensorial product of coherent states. It is found that this "trial" state constitutes a…

We discuss the classical and quantum mechanical evolution of systems described by a Hamiltonian that is a function of a solvable one, both classically and quantum mechanically. The case in which the solvable Hamiltonian corresponds to the…

Quantum Physics · Physics 2015-05-13 J. Fernando Barbero G. , Iñaki Garay , Eduardo J. S. Villaseñor

We study coherent states for Bianchi type I cosmological models, as examples of semiclassical states for time-reparametrization invariant systems. This simple model allows us to study explicitly the relationship between exact semiclassical…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Brett Bolen , Luca Bombelli , Alejandro Corichi

We consider the continuous-time version of our recently proposed quantum theory of optical temporal phase and instantaneous frequency [Tsang, Shapiro, and Lloyd, Phys. Rev. A 78, 053820 (2008)]. Using a state-variable approach to…

Quantum Physics · Physics 2009-05-21 Mankei Tsang , Jeffrey H. Shapiro , Seth Lloyd

Semiclassical techniques have proven to be a very powerful method to extract physical effects from different quantum theories. Therefore, it is expected that in the near future they will play a very prominent role in the context of quantum…

General Relativity and Quantum Cosmology · Physics 2014-12-17 David Brizuela

We study the classical and quantum perturbation theory for two non--resonant oscillators coupled by a nonlinear quartic interaction. In particular we analyze the question of quantum corrections to the torus quantization of the classical…

Quantum Physics · Physics 2007-05-23 Luca Salasnich

A variety of coherent states of the harmonic oscillator is considered. It is formed by a particular superposition of canonical coherent states. In the simplest case, these superpositions are eigenfunctions of the annihilation operator…

Quantum Physics · Physics 2009-10-30 V. Spiridonov

The center of mass motion of trapped ions and neutral atoms is suitable for approximation by a time-dependent driven quantum harmonic oscillator whose frequency and driving strength may be controlled with high precision. We show the time…

Quantum Physics · Physics 2024-03-25 E. García Herrera , F. Torres-Leal , B. M. Rodríguez-Lara

The coherent states for twist-deformed oscillator model provided in article [1] are constructed. Besides, it is demonstrated that the energy spectrum of considered model is labeled by two quantum numbers - by so-called main and azimutal…

Mathematical Physics · Physics 2015-06-19 Marcin Daszkiewicz , Cezary J. Walczyk

Given the Loop-Quantum-Gravity (LQG) non-graph-changing Hamiltonian $\widehat{H[N]}$, the coherent state expectation value $\langle\widehat{H[N]}\rangle$ admits an semiclassical expansion in $\ell^2_{\rm p}$. In this paper, we compute…

General Relativity and Quantum Cosmology · Physics 2022-05-17 Cong Zhang , Shicong Song , Muxin Han

We address the dynamics of nonclassicality for a quantum system interacting with a noisy fluctuating environment described by a classical stochastic field. As a paradigmatic example, we consider a harmonic oscillator initially prepared in a…

Quantum Physics · Physics 2015-10-27 Jacopo Trapani , Matteo Bina , Sabrina Maniscalco , Matteo G. A. Paris

We study some basic quantum confinement effects through investigation a deformed harmonic oscillator algebra. We show that spatial confinement effects on a quantum harmonic oscillator can be represented by a deformation function within the…

Quantum Physics · Physics 2009-05-20 M. Bagheri Harouni , R. Roknizadeh , M. H. Naderi

In a metric variable based Hamiltonian quantization, we give a prescription for constructing semiclassical matter-geometry states for homogeneous and isotropic cosmological models. These "collective" states arise as infinite linear…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Viqar Husain , Oliver Winkler