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Related papers: Spin relaxation in phase space

200 papers

We get fractional symmetric Fokker - Planck and Einstein - Smoluchowski kinetic equations, which describe evolution of the systems influenced by stochastic forces distributed with stable probability laws. These equations generalize known…

Statistical Mechanics · Physics 2009-10-31 A. V. Chechkin , V. Yu. Gonchar

Identifying quantum phase transitions poses a significant challenge in condensed matter physics, as this requires methods that both provide accurate results and scale well with system size. In this work, we demonstrate how relaxation…

Strongly Correlated Electrons · Physics 2026-02-11 David Jansen , Donato Farina , Luke Mortimer , Timothy Heightman , Andreas Leitherer , Pere Mujal , Jie Wang , Antonio Acín

We develop the concept of quantum phase-space (Wigner) distributions for quarks and gluons in the proton. To appreciate their physical content, we analyze the contraints from special relativity on the interpretation of elastic form factors,…

High Energy Physics - Phenomenology · Physics 2011-05-05 A. V. Belitsky , Xiangdong Ji , Feng Yuan

We reformulate the full quantum dynamics of spin systems using a phase space representation based on SU(2) coherent states which generates an exact mapping of the dynamics of any spin system onto a set of stochastic differential equations.…

Statistical Mechanics · Physics 2013-10-10 Ray Ng , Piotr Deuar , Erik Sorensen

We introduce a numerical method to simulate nonlinear open quantum dynamics of a particle in situations where its state undergoes significant expansion in phase space while generating small quantum features at the phase-space Planck scale.…

The concept of phase space distribution functions and their evolution is used in the case of en enlarged phase space. In particular, we include the intrinsic spin of particles and present a quantum kinetic evolution equation for a scalar…

Quantum Physics · Physics 2015-05-18 M. Marklund , J. Zamanian , G. Brodin

The Lindblad master equation for an open quantum system with a Hamiltonian containing an arbitrary potential is written as an equation for the Wigner distribution function in the phase space representation. The time derivative of this…

Quantum Physics · Physics 2008-11-26 A. Isar , A. Sandulescu , W. Scheid

We present an upgraded formula for Wigner function and spin polarization of fermions emitted by a relativistic fluid at local thermodynamic equilibrium at the decoupling which improves the one obtained in refs. [1, 2] and used in numerical…

Nuclear Theory · Physics 2026-01-23 Xin-Li Sheng , Francesco Becattini , Daniele Roselli

We relate a large class of classical spin models, including the inhomogeneous Ising, Potts, and clock models of q-state spins on arbitrary graphs, to problems in quantum physics. More precisely, we show how to express partition functions as…

Quantum Physics · Physics 2015-06-26 M. Van den Nest , W. Dür , H. J. Briegel

Relaxation schemes for finding normal modes of nonlinear excitations are described, and applied to the vortex-spinwave scattering problem in classical two-dimensional easy-plane Heisenberg models. The schemes employ the square of an…

Materials Science · Physics 2013-05-08 G. M. Wysin

We propose an approach to directly estimate the moments or marginals for a high-dimensional equilibrium distribution in statistical mechanics, via solving the high-dimensional Fokker-Planck equation in terms of low-order cluster moments or…

Numerical Analysis · Mathematics 2023-12-05 Yian Chen , Yuehaw Khoo , Lek-Heng Lim

A simple formula is derived for the maximum squeezing rate which occurs at the initial stages of the squeezing process: the rate only depends on the second partial derivatives of a classical Hamiltonian. Rules for optimum rotation of the…

Quantum Physics · Physics 2015-09-30 Tomáš Opatrný

A quantum phase space with Wannier basis is constructed: (i) classical phase space is divided into Planck cells; (ii) a complete set of Wannier functions are constructed with the combination of Kohn's method and L\"owdin method such that…

Quantum Physics · Physics 2018-03-02 Yuan Fang , Fan Wu , Biao Wu

We study continuous phase spaces of single spins and develop a complete description of their time evolution. The time evolution is completely specified by so-called star products. We explicitly determine these star products for general spin…

Quantum Physics · Physics 2019-01-11 Bálint Koczor , Robert Zeier , Steffen J. Glaser

As a natural extension of Fan's paper (arXiv: 0903.1769vl [quant-ph]) by employing the formula of operators' Weyl ordering expansion and the bipartite entangled state representation we find new two-fold complex integration transformation…

Quantum Physics · Physics 2015-05-14 Hong-yi Fan , Hong-chun Yuan

We review the Weyl-Wigner formulation of quantum mechanics in phase space. We discuss the concept of Narcowich-Wigner spectrum and use it to state necessary and sufficient conditions for a phase space function to be a Wigner distribution.…

High Energy Physics - Theory · Physics 2009-11-11 Nuno Costa Dias , Joao Nuno Prata

In the Wigner-Weyl phase space formulation of quantum mechanics, we analyse the problem of the spreading of an initial state or an initial operator under time evolution when described in terms of the Krylov basis. After constructing the…

Quantum Physics · Physics 2026-03-18 Kunal Pal , Kuntal Pal , Keun-Young Kim

The spin relaxation time in solids is determined by several competing energy scales and processes and distinct methods are called for to analyze the various regimes. We present a stochastic model for the spin dynamics in solids which is…

Strongly Correlated Electrons · Physics 2020-07-22 G. Csosz , L. Szolnoki , A. Kiss , B. Dora , F. Simon

A phase space formulation of the filtering process upon an incident quantum state is developed. This formulation can explain the results of both quantum interference and delayed-choice experiments without making use of the controversial…

Quantum Physics · Physics 2009-11-10 Daniela Dragoman

In the usual formulation of quantum mechanics, groups of automorphisms of quantum states have ray representations by unitary and antiunitary operators on complex Hilbert space, in accordance with Wigner's Theorem. In the phase-space…

Mathematical Physics · Physics 2017-02-23 A. J. Bracken , G. Cassinelli , J. G. Wood