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arXiv · 0907.3507

Analysis of Kapitza-Dirac diffraction patterns beyond the Raman-Nath regime

Bryce Gadway·Daniel Pertot·Rene Reimann·Martin G. Cohen·Dominik Schneble
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Abstract

We study Kapitza-Dirac diffraction of a Bose-Einstein condensate from a standing light wave for a square pulse with variable pulse length but constant pulse area. We find that for sufficiently weak pulses, the usual analytical short-pulse prediction for the Raman-Nath regime continues to hold for longer times, albeit with a reduction of the apparent modulation depth of the standing wave. We quantitatively relate this effect to the Fourier width of the pulse, and draw analogies to the Rabi dynamics of a coupled two-state system. Our findings, combined with numerical modeling for stronger pulses, are of practical interest for the calibration of optical lattices in ultracold atomic systems.

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Bryce Gadway, Daniel Pertot, Rene Reimann, Martin G. Cohen, Dominik Schneble. 2009-07-20. Analysis of Kapitza-Dirac diffraction patterns beyond the Raman-Nath regime. https://doi.org/10.1364/oe.17.019173

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