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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

The semiclassical formula for the quantum propagator in the coherent state representation $<\mathbf{z}'' | e^{-i\hat{H}T/\hbar} | \mathbf{z}'>$ is not free from the problem of caustics. These are singular points along the complex classical…

Quantum Physics · Physics 2008-03-03 A. D. Ribeiro , M. A. M. de Aguiar

A detailed derivation of the semiclassical propagator in the generalized coherent-state representation is performed by applying the saddle-point method to a path integral over the classical phase space. With the purpose of providing greater…

Quantum Physics · Physics 2015-10-21 Thiago F. Viscondi , Adriano Grigolo , Marcus A. M. de Aguiar

We construct a representation of the coherent state path integral using the Weyl symbol of the Hamiltonian operator. This representation is very different from the usual path integral forms suggested by Klauder and Skagerstan in…

Quantum Physics · Physics 2009-11-13 L. C. dos Santos , M. A. M. de Aguiar

We derive the semiclassical limit of the coherent state propagator for systems with two degrees of freedom of which one degree of freedom is canonical and the other a spin. Systems in this category include those involving spin-orbit…

Quantum Physics · Physics 2009-11-11 A. D. Ribeiro , M. A. M. de Aguiar , A. F. R. de Toledo Piza

The semiclassical approximation to the coherent state propagator requires complex classical trajectories in order to satisfy the associated boundary conditions, but finding these trajectories in practice is a difficult task that may…

Quantum Physics · Physics 2007-12-04 Marcel Novaes

We discuss some basic tools for an analysis of one-dimensionalquantum systems defined on a cyclic coordinate space. The basic features of the generalized coherent states, the complexifier coherent states are reviewed. These states are then…

Quantum Physics · Physics 2008-11-26 B. Bahr , H. J. Korsch

In this work, we derived a semiclassical approximation for the matrix elements of a quantum propagator in coherent states (CS) basis that avoids complex trajectories, it only involves real ones. For that propose, we used the, symplectically…

Quantum Physics · Physics 2015-06-05 Alejandro M. F Rivas

We present an Initial Value Representation for the semiclassical coherent state propagator based on complex trajectories. We map the complex phase space into a real phase space with twice as many dimensions and use a simple procedure to…

Quantum Physics · Physics 2009-08-14 Marcus A. M. de Aguiar , Silvio A. Vitiello , Adriano Grigolo

The semiclassical propagation of spin coherent states is considered in complex phase space. For two time-independent systems we find the appropriate classical trajectories and show that their combined contributions are able to describe…

Quantum Physics · Physics 2007-12-04 M. Novaes

We assess the suitability of quantum and semiclassical initial value representations, exemplified by the coupled coherent states (CCS) method and the Herman Kluk (HK) propagator, respectively, for modeling the dynamics of an electronic wave…

Atomic Physics · Physics 2015-06-19 C. Zagoya , J. Wu , M. Ronto , D. V. Shalashilin , C. Figueira de Morisson Faria

We consider a semiclassical approximation for the time evolution of an originally gaussian wave packet in terms of complex trajectories. We also derive additional approximations replacing the complex trajectories by real ones. These yield…

Quantum Physics · Physics 2009-11-10 M. A. M. de Aguiar , M. Baranger , L. Jaubert , Fernando Parisio , A. D. Ribeiro

The semiclassical approximation of coherent state path integrals is employed to study the dynamics of the Jaynes-Cummings model. Decomposing the Hilbert space into subspaces of given excitation quanta above the ground state, the…

Quantum Physics · Physics 2009-11-06 Adrian Alscher , Hermann Grabert

The overcompleteness of the coherent states basis leads to a multiplicity of representations of Feynman's path integral. These different representations, although equivalent quantum mechanically, lead to different semiclassical limits. Two…

Quantum Physics · Physics 2007-05-23 Luis C. dos Santos , M. A. M. de Aguiar

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

A uniform approximation for the coherent state propagator, valid in the vicinity of phase space caustics, was recently obtained using the Maslov method combined with a dual representation for coherent states. In this paper we review the…

Quantum Physics · Physics 2015-05-13 A D Ribeiro , M A M de Aguiar

As a model for the semiclassical analysis of quantum-mechanical systems with both potentials and boundary conditions, we construct the WKB propagator for a linear potential sloping away from an impenetrable boundary. First, we find all…

Quantum Physics · Physics 2017-03-08 T. A. Zapata , S. A. Fulling

A semiclassical formula for the coherent-state propagator requires the determination of specific classical paths inhabiting a complex phase-space through a Hamiltonian flux. Such trajectories are constrained to special boundary conditions…

Quantum Physics · Physics 2017-02-01 A. L. Xavier

By revisiting the path-integral formulation of the Hubbard model, we propose a theoretical approach based on a semiclassical approximation employing an unconventional coherent-state representation. Within this framework, a subset of the…

Strongly Correlated Electrons · Physics 2026-04-06 Yuki Yamasaki , Hidemaro Suwa , Cristian D. Batista , Shintaro Hoshino

A unified viewpoint on the van Vleck and Herman-Kluk propagators in Hilbert space and their recently developed counterparts in Wigner representation is presented. It is shown that the numerical protocol for the Herman-Kluk propagator, which…

Chemical Physics · Physics 2018-03-14 Fabian Gottwald , Sergei D. Ivanov
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