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Physical Review A

Phase change of a probe due to oscillation of cold atoms in an optical standing wave

Mikio Kozuma, Ken-ichi Nakagawa, Wonho Jhe, Motoichi Ohtsu

Published Jan 1, 1998• 6 citations
Publisher

Abstract

We abruptly subject laser-cooled ${}^{87}\mathrm{Rb}$ atoms to the one-dimensional, blue-detuned, optical standing-wave potential generated by two crossed probe laser beams and detect the phase change of the probe beam due to cold-atom dynamics. Damped oscillations of the observed phase signal are attributed to a temporal change of the root-mean-square position of the cold atoms relative to the minima of the periodic optical potential. The damping rate is in good agreement with numerical results, which take into account the potential anharmonicity but neglect spontaneous emission. The agreement indicates that the decay is mainly caused by dephasing due to trap anharmonicity. For sufficient low initial temperature, our calculations show quantum revivals of the wave-packet oscillation.

DOI
10.1103/physreva.57.r24

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