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Gauge invariance and wave packet simulations in the presence of dipole fields

Thierry Martin
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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.

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Thierry Martin. 1994-09-07. Gauge invariance and wave packet simulations in the presence of dipole fields. https://doi.org/10.1016/0921-4526(95)00374-i

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