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Coherence-enhanced imaging of a degenerate Bose gas

L. E. Sadler·J. M. Higbie·S. R. Leslie·M. Vengalattore·D. M. Stamper-Kurn
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Abstract

We present coherence-enhanced imaging, an in situ technique that uses Raman superradiance to probe the spatial coherence properties of an ultracold gas. Applying this method, we obtain a spatially resolved measurement of the condensate number and more generally, of the first-order spatial correlation function in a gas of $^{87}$Rb atoms. We observe the enhanced decay of propagating spin gratings in high density regions of a Bose condensate, a decay we ascribe to collective, non-linear atom-atom scattering. Further, we directly observe spatial inhomogeneities that arise generally in the course of extended sample superradiance.

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L. E. Sadler, J. M. Higbie, S. R. Leslie, M. Vengalattore, D. M. Stamper-Kurn. 2006-09-01. Coherence-enhanced imaging of a degenerate Bose gas. https://doi.org/10.1103/physrevlett.98.110401

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