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Related papers: Squeezed states and Symplectic transformations

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In the previous paper, we adopted the method using quantum mutual entropy to measure the degree of entanglement in the time development of the Jaynes-Cummings model. In this paper, we formulate the entanglement in the time development of…

Quantum Physics · Physics 2009-11-07 Shigeru Furuichi , Mahmoud Abdel-Aty

In this paper we study the application of four-mode squeezed states in the cosmological context, studying two weakly coupled scalar fields in the planar patch of the de Sitter space. We construct the four-mode squeezed state formalism and…

General Relativity and Quantum Cosmology · Physics 2022-12-13 Sayantan Choudhury , Sudhakar Panda , Nilesh Pandey , Abhishek Roy

Mesoscopic superpositions of distinguishable coherent states provide an analog to the Schr\"odinger's cat thought experiment. For mechanical oscillators these have primarily been realised using coherent wavepackets, for which the…

Using Baker-Campbell-Hausdorff relations, the squeeze and harmonic-oscillator time-displacement operators are given in the form $\exp[\delta I] \exp[\alpha (x^2)]\exp[\beta(x\partial)] \exp[\gamma (\partial)^2]$, where $\alpha$, $\beta$,…

Quantum Physics · Physics 2016-09-08 Michael Martin Nieto

We study the time evolution of entangled states of a pair of identical atoms, considered in the harmonic approximation, coupled to an environment represented by an infinite set of free oscillators, with the whole system confined within a…

Quantum Physics · Physics 2015-06-03 E. G. Figueiredo , C. A. Linhares , A. P. C. Malbouisson , J. M. C. Malbouisson

We investigate the evolution of the phase-space distribution function around slightly perturbed stationary states and the process of violent relaxation in the context of the dissipationless collapse of an isolated spherical self-gravitating…

Astrophysics of Galaxies · Physics 2022-03-02 Luca Barbieri , Pierfrancesco Di Cintio , Guido Giachetti , Alicia Simon-Petit , Lapo Casetti

Quantum sensing and quantum information processing use quantum advantages such as squeezed states that encode a quantity of interest with higher precision and generate quantum correlations to outperform classical methods. In harmonic…

Quantum Physics · Physics 2021-10-28 Mingjie Xin , Wui Seng Leong , Zilong Chen , Yu Wang , Shau-Yu Lan

In the coordinate representation of thermofield dynamics, we investigate the thermalized displaced squeezed thermal state which involves two temperatures successively. We give the wavefunction and the matrix element of the density operator…

Quantum Physics · Physics 2008-11-26 Wen-Fa Lu

We consider a class of space-time coupled evolution equations (CEEs), obtained by a subordination of the heat operator. Our CEEs reformulate and extend known governing equations of non-Markovian processes arising as scaling limits of…

Analysis of PDEs · Mathematics 2019-03-12 John Herman , Ifan Johnston , Lorenzo Toniazzi

We analyze the properties and dynamics of generalized squeezed states. We find that, in stark contrast to displacement and two-photon squeezing, higher-order squeezing leads to oscillatory dynamics. The state is squeezed in the initial…

Quantum Physics · Physics 2025-08-25 Sahel Ashhab , Mohammad Ayyash

In this work, we have applied the integrals of motion method in a nonunitary approach and so obtained the time-dependent displacement and squeezed parameters of the coherent squeezed states (CSS). On its turn, CSS for one-dimensional…

Quantum Physics · Physics 2021-05-21 A. S. Pereira , A. S. Lemos

In this work, we make use of Lie algebraic methods to obtain the time evolution operator for an optomechanical system with linear and quadratic couplings between the field and the mechanical oscillator. Firstly, we consider the case of a…

Quantum Physics · Physics 2025-04-25 Luis A. Medina-Dozal , Alejandro R. Urzúa , José Récamier-Angelini

For a time-dependent harmonic oscillator with an inverse squared singular term, we find the generalized invariant using the Lie algebra of $SU(2)$ and construct the number-type eigenstates and the coherent states using the…

Quantum Physics · Physics 2007-05-23 Jung Kon Kim , Sang Pyo Kim

We apply the formalism of coherent states in quantum optics to pomeron evolution and show that evolving squeezed pomeron states are equivalent to pomeron fan diagrams at the leading order of perturbative expansion. Based on our results, we…

High Energy Physics - Phenomenology · Physics 2025-08-05 Dima Cheskis , Alex Prygarin

An abstract 2nd-order evolution equation or inclusion is discretised in time in such a way that the energy is conserved at least in qualified cases, typically in the cases when the governing energy is component-wise quadratic or…

Numerical Analysis · Mathematics 2016-06-01 Tomas Roubicek , Christos G. Panagiotopoulos

The role of the spatiotemporal degrees of freedom in the preparation and observation of squeezed photonic states, produced by parametric down-conversion, is investigated. The analysis is done with the aid of a functional approach under the…

Quantum Physics · Physics 2021-01-13 Filippus S. Roux

In this paper we propose the idea that there is a corresponding relation between quantum states and points of the complex projective space, given that the number of dimensions of the Hilbert space is finite. We check this idea through…

Mathematical Physics · Physics 2007-05-23 Bei Jia , Xi-guo Lee

We give a detailed theory for the leading coarse-grained dynamics of entanglement entropy of states and of operators in generic short-range interacting quantum many-body systems. This includes operators spreading under Heisenberg time…

Statistical Mechanics · Physics 2018-03-02 Cheryne Jonay , David A. Huse , Adam Nahum

Partial symplectic conditional and joint probability representations of quantum mechanics are considered. The correspondence rules for most interesting physical operators are found and the expressions of the dual symbols of operators are…

Quantum Physics · Physics 2024-06-12 Ya. A. Korennoy , V. I. Man'ko

In the present work, a new time-dependent exchange theory is presented wherein the symmetry constraints, on a multi-electron wavefunction, are properly accounted for. In so doing, the equations of motion, incorporating the required…

Computational Physics · Physics 2007-05-23 Charles A. Weatherford