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arXiv · 1401.2156

The effect of Landau-Zener tunnelings on the nonlinear dynamics of cold atoms in a modulated laser field

Victor Argonov
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Abstract

We study the motion of a cold atom in a frequency-modulated standing laser wave. If the detuning between the atomic electronic transition and the field is large, the atom moves in a modulated optical potential demonstrating known classical nonlinear effects such as chaos and nonlinear resonances. If the atom-field detuning is small, then two optical potentials emerge in the system, and the atom performs Landau-Zener (LZ) tunnelings between them. It is a radically non-classical behavior. However, we show that classical nonlinear structures in system's phase space (KAM-tori and chaotic layers) survive. Quantum effect of LZ tunnelings only induces small random jumps of trajectories between these structures (dynamical tunneling).

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Victor Argonov. 2014-01-09. The effect of Landau-Zener tunnelings on the nonlinear dynamics of cold atoms in a modulated laser field. https://arxiv.org/abs/1401.2156

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