A driven two-component BEC: Chaos in a Macroscopic Quantum System

Jiří Tomkovič

Published Jan 1, 2014• 0 citations

Abstract

This work discusses the experimental realization of a mixed regular-chaotic phase space in a macroscopic quantum system. The effective Planck's constant of the system can be varied in a large range. Therefore, the semi-classical limit of the system can be studied, where the initial size of the many particle wave packet is much smaller than typical structures of the phase space. Thus, different structures of the phase space can be resolved. In a weakly driven system, the Poincaré-Birkhoff scenario is investigated by the dispersion of the wave packet at a stable or unstable fixed point. In a strongly driven system, different dynamics of a wave packet is found, dependent on preparation in a regular island or the chaotic sea. The time evolution can be described by a classical model, which is in good agreement with experiment as well as the mean field model for the considered observables. \n \nIn an independent experiment using an atomic beam setup the generation of motional coherence of a single atom by spontaneous emission of a single photon has been demonstrated.

DOI: 10.11588/heidok.00016256

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