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Related papers: Variational Truncated Wigner Approximation

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The applicability of the so-called truncated Wigner approximation (-W) is extended to multitime averages of Heisenberg field operators. This task splits naturally in two. Firstly, what class of multitime averages the -W approximates, and,…

Statistical Mechanics · Physics 2009-09-30 B. Berg , L. I. Plimak , A. Polkovnikov , M. K. Olsen , M. Fleischhauer , W. P. Schleich

We propose a new minimum-distance estimator for linear random coefficient models. This estimator integrates the recently advanced sliced Wasserstein distance with the nearest neighbor methods, both of which enhance computational efficiency.…

Statistics Theory · Mathematics 2025-04-25 Keunwoo Lim , Ting Ye , Fang Han

We propose a Wigner quasiprobability distribution function for Hamiltonian systems in spaces of constant curvature --in this paper on hyperboloids--, which returns the correct marginals and has the covariance of the Shapiro functions under…

Quantum Physics · Physics 2015-06-26 Miguel Angel Alonso , George S. Pogosyan , Kurt Bernardo Wolf

Quantum state processing is one of the main tools of quantum technologies. While real systems are complicated and/or may be driven by non-ideal control they may nevertheless exhibit simple dynamics approximately confined to a low-energy…

Quantum Physics · Physics 2023-06-21 Nicola Macrì , Luigi Giannelli , Elisabetta Paladino , Giuseppe Falci

This paper presents a useful compact formula for deriving an effective Hamiltonian describing the time-averaged dynamics of detuned quantum systems. The formalism also works for ensemble-averaged dynamics of stochastic systems. To…

Quantum Physics · Physics 2009-11-13 Daniel F. V. James , Jonathan Jerke

The \emph{semiclassical Wigner treatment} of Brown and Heller [J. Chem. Phys. 75, 186 (1981)] is applied to triatomic direct photodissociations with the aim of accurately predicting final state distributions at relatively low computational…

Chemical Physics · Physics 2017-09-13 W. Arbelo-González , L. Bonnet , A. García-Vela

In this work we present the simplest generic form of the propagator for the time-dependent quadratic Hamiltonian. We manifest the simplicity of our method by giving explicitly the propagators for a free particle in time-dependent electric…

Quantum Physics · Physics 2014-12-12 Gal Harari , Yacob Ben-Aryeh , Ady Mann

We study discrete-time $(m,n)$-multirate systems on separable Hilbert spaces, solving the problem of approximating such a system by one which has a shorter multirate period $(m/q,n/q)$, optimally in the Hilbert-Schmidt norm. We work in the…

Optimization and Control · Mathematics 2020-05-05 Mikael Kurula

We study smooth, caustic-free, chaotic semiclassical dynamics on two-dimensional phase space and find that the dynamics can be approached by an iterative procedure which constructs an approximation to the exact long-time semiclassical…

chao-dyn · Physics 2009-08-14 L. Kaplan

We present a phase space study of non-Hermitian Hamiltonian with $\mathcal{PT}$-symmetry based on the Wigner distribution function. For an arbitrary complex potential, we derive a generalized continuity equation for the Wigner function flow…

Quantum Physics · Physics 2016-05-25 Ludmila Praxmeyer , Popo Yang , Ray-Kuang Lee

The spin coherent state path integral describing the dynamics of a spin-1/2-system in a magnetic field of arbitrary time-dependence is considered. Defining the path integral as the limit of a Wiener regularized expression, the semiclassical…

Quantum Physics · Physics 2008-11-26 Adrian Alscher , Hermann Grabert

By use of the recently derived $universal$ discrete imaginary-time propagator of the harmonic oscillator, both thermodynamic and Hamiltonian energies can be given analytically, and evaluated numerically at each imaginary time step, for…

Quantum Physics · Physics 2024-07-01 Siu A. Chin

We derive an effective spin Hamiltonian for the one-dimensional half-filled asymmetric ionic Hubbard model with alternating on-site interaction in the limit of strong repulsion. It is shown that the effective Hamiltonian is that of a spin…

Strongly Correlated Electrons · Physics 2016-02-01 Inna Grusha , Mikheil Menteshashvili , George I. Japaridze

The discretization approximation method commonly used to simulate the dynamics of quantum system coupled to the environment in continuum often suffers from the periodically partial recovery of initial state because of the effect of finite…

Quantum Physics · Physics 2025-05-07 H. T. Cui , Y. A. Yan , M. Qin , X. X. Yi

A semiclassical approximation is derived by using a family of wavepackets to map arbitrary wavefunctions into phase space. If the Hamiltonian can be approximated as linear over each individual wavepacket, as often done when presenting…

Quantum Physics · Physics 2024-04-30 Clay D. Spence

We use spin-coherent states as a time-dependent variational ansatz for a semiclassical description of a large family of Heisenberg models. In addition to common approaches we also evaluate the square variance of the Hamiltonian in terms of…

Condensed Matter · Physics 2009-10-31 John Schliemann , Franz G. Mertens

Efficient and accurate numerical propagation of the time dependent Schroedinger equation is a problem with applications across a wide range of physics. This paper develops an efficient, trivially parallelizeable method for relaxing a trial…

Computational Physics · Physics 2011-11-21 Zachary B. Walters

Effective Hamiltonian methods are utilized to model the two-qubit cross-resonance gate for both the ideal two-qubit case and when higher levels are included. Analytic expressions are obtained in the qubit case and the higher-level model is…

Quantum Physics · Physics 2020-05-13 Easwar Magesan , Jay M. Gambetta

We present a semiclassical phase-space method to calculate thermal and ground states of large interacting spin systems. To this end, we extend the recently developed truncated Wigner approximation for spins (TWA) to the imaginary time,…

Quantum Physics · Physics 2026-03-05 Tom Schlegel , Dennis Breu , Michael Fleischhauer

We present a semiclassical analysis of the quantum propagator of a particle confined on one side by a steeply, monotonically rising potential. The models studied in detail have potentials proportional to $x^{\alpha}$ for $x>0$; the limit…

Mathematical Physics · Physics 2013-06-05 F. D. Mera , S. A. Fulling , J. D. Bouas , K. Thapa