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Related papers: Improved semiclassical density matrix: taming caus…

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We present a simple method to deal with caustics in the semiclassical approximation to the partition function of a one-dimensional quantum system. The procedure, which makes use of complex trajectories, is applied to the quartic double-well…

Statistical Mechanics · Physics 2007-05-23 C. A. A. de Carvalho , R. M. Cavalcanti , E. S. Fraga , S. E. Joras

Employing the path integral approach, we calculate the semiclassical equilibrium density matrix of a particle moving in a nonlinear potential field for coordinates near the top of a potential barrier. As the temperature is decreased, near a…

Quantum Physics · Physics 2015-06-26 F. J. Weiper , J. Ankerhold , H. Grabert

We present a barrier potential with bound states that is exactly solvable and determine the eigenfunctions and eigenvalues of the Hamiltonian. The equilibrium density matrix of a particle moving at temperature T in this nonlinear barrier…

chem-ph · Physics 2009-10-28 Franz Josef Weiper , Joachim Ankerhold , Hermann Grabert

We compute the partition function and specific heat for a quantum mechanical particle under the influence of a quartic double-well potential non-perturbatively, using the semiclassical method. Near the region of bounded motion in the…

High Energy Physics - Phenomenology · Physics 2014-07-23 D. Kroff , A. Bessa , C. A. A. de Carvalho , E. S. Fraga , S. E. Jorás

We present a semiclassical trace formula for the canonical partition function of arbitrary one-dimensional systems. The approximation is obtained via the stationary exponent method applied to the phase-space integration of the density…

Quantum Physics · Physics 2007-05-23 Fernando Parisio , M. A. M. de Aguiar

We derive the semiclassical series for the partition function of a one-dimensional quantum-mechanical system consisting of a particle in a single-well potential. We do this by applying the method of steepest descent to the path-integral…

Quantum Physics · Physics 2009-10-31 C. A. A. de Carvalho , R. M. Cavalcanti , E. S. Fraga , S. E. Joras

A new variational method for studying the equilibrium states of an interacting particles system has been proposed. The statistical description of the system is realized by means of a density matrix. This method is used for description of…

General Physics · Physics 2014-12-19 Boris Bondarev

We use a semiclassical approximation to derive the partition function for an arbitrary potential in one-dimensional Quantum Statistical Mechanics, which we view as an example of finite temperature scalar Field Theory at a point. We rely on…

Quantum Physics · Physics 2009-10-31 C. A. A. de Carvalho , R. M. Cavalcanti

We use a path integral formalism to derive the semiclassical series for the partition function of a particle in D dimensions. We analyze in particular the case of attractive central potentials, obtaining explicit expressions for the…

Quantum Physics · Physics 2009-10-31 C. A. A. de Carvalho , R. M. Cavalcanti , E. S. Fraga , S. E. Jorás

Semiclassical periodic orbit theory is used in many branches of physics. However, most applications of the theory have been to systems which involve only single particle dynamics. In this work, we develop a semiclassical formalism to…

Chaotic Dynamics · Physics 2009-10-31 Jamal Sakhr , Niall D. Whelan

We describe a semiclassical method to calculate universal transport properties of chaotic cavities. While the energy-averaged conductance turns out governed by pairs of entrance-to-exit trajectories, the conductance variance, shot noise and…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Sebastian Müller , Stefan Heusler , Petr Braun , Fritz Haake

Semiclassical transition probabilities characterize transfer of energy between "hard" and "soft" modes in various physical systems. We establish the boundary problem for singular euclidean solutions used to calculate such probabilities.…

High Energy Physics - Phenomenology · Physics 2009-10-28 S. Yu. Khlebnikov

We use a deterministic particle method to produce numerical approximations to the solutions of an evolution cross-diffusion problem for two populations. According to the values of the diffusion parameters related to the intra and…

Numerical Analysis · Mathematics 2024-01-29 Gonzalo Galiano , Virginia Selgas

A consistent analytical approach for calculation of the quasiclassical radial dipole matrix elements in the momentum and coordinate representations is presented. Very simple but relatively precise expressions for the matrix elements are…

Atomic Physics · Physics 2008-02-03 B. Kaulakys

We consider the problem of a semiclassical description of quantum chaotic transport, when a tunnel barrier is present in one of the leads. Using a semiclassical approach formulated in terms of a matrix model, we obtain transport moments as…

Chaotic Dynamics · Physics 2022-07-06 Pedro H. S. Bento , Marcel Novaes

We discuss the semiclassical approximation to transport problems in quantum chaotic systems. The figures of merit are moments of the transmission matrix and of the time delay matrix. After reviewing a few results obtained by treating these…

Quantum Physics · Physics 2026-04-16 Marcel Novaes

The semiclassical formula for the coherent-state propagator is written in terms of complex classical trajectories of an equivalent classical system. Depending on the parameters involved, more than one trajectory may contribute to the…

Quantum Physics · Physics 2015-05-19 A. D. Ribeiro

Classical density-functional theory is employed to study finite-temperature trends in the relative stabilities of one-component quasicrystals interacting via effective metallic pair potentials derived from pseudopotential theory. Comparing…

Materials Science · Physics 2009-10-30 A. R. Denton , J. Hafner

A simple position probability density formulation is presented for the motion of a particle in a spherically symmetric potential. The approach provides an alternative to Newtonian methods for presentation in an elementary course, and…

Physics Education · Physics 2007-05-23 Lorenzo J. Curtis , David G. Ellis

A thorough account is given of the derivation of uniform semiclassical approximations to the particle and kinetic energy densities of N noninteracting bounded fermions in one dimension. The employed methodology allows the inclusion of…

Quantum Physics · Physics 2015-10-21 Raphael F. Ribeiro , Kieron Burke
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