Gauge invariance and wave packet simulations in the presence of dipole fields
arXiv:cond-mat/9409030 · doi:10.1016/0921-4526(95)00374-I
Abstract
A method for performing wave packet simulations in dipole fields is presented. Starting from a Hamiltonian with non commuting terms, a gauge transformation leads to a new Hamiltonian which allows to calculate explicitly the evolution operator. In this new gauge, the dipole field is fully included in the {\it vector} potential. The method of Goldberg, Schwartz and Schey based on the Caley form of the evolution operator is then generalized, and the resulting scheme is applied to describe a switching device based on Rabi oscillations. The probability to tunnel in the free region exhibits a plateaux structure as the wave function is emitted by ``bursts'' after each Rabi oscillation has been completed.
4 pages (Revtex 3.0), figures upon request, LA-UR-94-3035