Phase contrast imaging of Bose condensed clouds

R. Meppelink; R. A. Rozendaal; S. B. Koller; J. M. Vogels; P. van der Straten

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arXiv · 0909.4429

Phase contrast imaging of Bose condensed clouds

R. Meppelink·R. A. Rozendaal·S. B. Koller·J. M. Vogels·P. van der Straten

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Abstract

Phase contrast imaging is used to observe Bose-Einstein condensates (BECs) at finite temperature in situ. The imaging technique is used to accurately derive the absolute phase shift of a probe laser beam due to both the condensate and the thermal cloud. The accuracy of the method is enhanced by using the periodicity of the intensity signal as a function of the accumulated phase. The measured density profiles can be described using a two relevant parameter fit, in which only the chemical potential and the temperature are to be determined. This allows us to directly compare the measured density profiles to different mean-field models in which the interaction between the condensed and thermal atoms is taken into account to various degrees.

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R. Meppelink, R. A. Rozendaal, S. B. Koller, J. M. Vogels, P. van der Straten. 2009-09-24. Phase contrast imaging of Bose condensed clouds. https://arxiv.org/abs/0909.4429

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