Three-dimensional spin-dependent dynamics in linearly polarized standing-wave fields

Abstract

There is a revival of the problem of how a relativistic particle with spin moves through an electromagnetic field. Our paper focuses on the spin-dependent dynamics of electrons in linearly polarized laser fields based on the Dirac equation and a classical spin model. It is proved that an electron at rest undergoes a three-dimensional motion moving out of the polarization-propagation plane when the initial spin is perpendicular to the magnetic field. We make a comprehensive investigation of the dynamics of quantum wave packets and classical electrons in both plane-wave and standing-wave fields. The wave packet travels in accordance with its center of mass in a plane-wave field but spreads heavily in a standing-wave field. The ensembles of classical electrons turn out to well simulate the quantum wave-packet dynamics in the standing-wave fields. We give the extended calculations of the electron dynamics with spin in the standing-wave field in the chaotic regime and find the quantum correspondence to the classical chaotic dynamics.