Dynamical properties of spin and subbands populations in 1D quantum wire

Abstract

AbstractIn this paper we study the spin and subbands populations, as functions of time, for electrons in a quasi‐1D quantum wire, with spin–orbit coupling (SOC), to which a perpendicular magnetic field is applied. The system is governed by the Hamiltonian which, in the strong magnetic field limit, resembles the Jaynes–Cummings model (JCM) in quantum optics (QO). Using a procedure similar to that in QO, we explicitly present the time‐evolution operator, thereby calculating the spin states and subbands populations as functions of time. We show that the populations exhibit oscillations, depending on the interaction parameters, scale lengths and, particularly, the initial states of the system. Specifically, if the electrons are initially prepared in a maximal coherent superposition of spin states, the expectation values periodically collapse and revive. The collapse‐revivals are most profound for the spin along the magnetic field and subbands populations. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)