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arXiv · 1607.02934

Measurement-enhanced determination of BEC phase transitions

Mark G. Bason·Robert Heck·Mario Napolitano·Ottó Elíasson·Romain Müller·Aske Thorsen·Wen-Zhuo Zhang·Jan Arlt·Jacob F. Sherson
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Abstract

We demonstrate how dispersive atom number measurements during evaporative cooling can be used for enhanced determination of the parameter dependence of the transition to a Bose-Einstein condensate (BEC). In this way shot-to-shot fluctuations in initial conditions are detected and the information extracted per experimental realization is increased. We furthermore calibrate in-situ images from dispersive probing of a BEC with corresponding absorption images in time-of-flight. This allows for the determination of the transition point in a single experimental realization by applying multiple dispersive measurements. Finally, we explore the continuous probing of several consecutive phase transition crossings using the periodic addition of a focused "dimple" potential.

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Mark G. Bason, Robert Heck, Mario Napolitano, Ottó Elíasson, Romain Müller, Aske Thorsen, Wen-Zhuo Zhang, Jan Arlt, Jacob F. Sherson. 2018-03-26. Measurement-enhanced determination of BEC phase transitions. https://doi.org/10.1088/1361-6455%2Faad447

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