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Elementary excitations of trapped Bose gas in the large-gas-parameter regime

Arup Banerjee·Manoranjan P. Singh
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Abstract

We study the effect of going beyond the Gross-Pitaevskii theory on the frequencies of collective oscillations of a trapped Bose gas in the large gas parameter regime. We go beyond the Gross-Pitaevskii regime by including a higher-order term in the interatomic correlation energy. To calculate the frequencies we employ the sum-rule approach of many-body response theory coupled with a variational method for the determination of ground-state properties. We show that going beyond the Gross-Pitaevskii approximation introduces significant corrections to the collective frequencies of the compressional mode.

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Arup Banerjee, Manoranjan P. Singh. 2002-08-30. Elementary excitations of trapped Bose gas in the large-gas-parameter regime. https://doi.org/10.1103/physreva.66.043609

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