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Experimental investigation of early-time diffusion in the quantum kicked rotor using a Bose-Einstein condensate

G. Duffy·S. Parkins·T. Muller·M. Sadgrove·R. Leonhardt·A. C. Wilson
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Abstract

We report the experimental observation of resonances in the early-time momentum diffusion rates for the atom-optical delta-kicked rotor. In this work a Bose-Einstein condensate provides a source of ultra-cold atoms with an ultra-narow initial momentum distribution, which is then subjected to periodic pulses (or "kicks") using an intense far-detuned optical standing wave. A quantum resonance occurs when the momentum eigenstates accumulate the same phase between kicks leading to ballistic energy growth. Conversely, an anti-resonance is observed when the phase accumulated from successive kicks cancels and the system returns to its initial state. Our experimental results are compared with theoretical predictions.

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G. Duffy, S. Parkins, T. Muller, M. Sadgrove, R. Leonhardt, A. C. Wilson. 2004-05-31. Experimental investigation of early-time diffusion in the quantum kicked rotor using a Bose-Einstein condensate. https://doi.org/10.1103/physreve.70.056206

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