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Temperature-Dependent Frequency Shifts in Collective Excitations of a Bose-Einstein Condensate

Hualin Shi·Wei-Mou Zheng
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Abstract

By including the contribution of the thermal cloud to the Lagrangian of the condensate of a Bose gas, we extend the time-dependent variational method at zero temperature to study temperature-dependent low collective excitation modes. A Gaussian trial wave function of the condensate and a static distribution density of the thermal cloud are used, and analytical expressions for temperature-dependent excitation frequencies obtained. Theoretical results are compared with measurements in the JILA and MIT experiments.

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Hualin Shi, Wei-Mou Zheng. 1998-04-09. Temperature-Dependent Frequency Shifts in Collective Excitations of a Bose-Einstein Condensate. https://doi.org/10.1103/physreva.59.1562

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