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arXiv · 1402.6977

Imaging cold atoms with shot-noise and diffraction limited holography

J. P. Sobol·Saijun Wu
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Abstract

We theoretically develop and experimentally demonstrate a holographic method for imaging cold atoms at the diffraction and photon shot noise limits. Aided by a double point source reference field, a simple iterative algorithm robustly removes the twin image of an $^{87}$Rb cold atom sample during the image reconstruction. Shot-noise limited phase shift and absorption images are consistently retrieved at various probe detunings, and during the laser cooling process. We consistently resolve less than 2 mrad phase shift ($0.4~\%$ attenuation) of the probe light, outperforming shot-noise limited phase-contrast (absorption) imaging by a factor of 4 or more if the same camera is used without pixel saturation. We discuss the possible extension of this work for precise phase imaging of dense atomic gases, and for off-resonant probing of multiple atoms in optical lattices.

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J. P. Sobol, Saijun Wu. 2014-02-27. Imaging cold atoms with shot-noise and diffraction limited holography. https://doi.org/10.1088/1367-2630/16/9/093064

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