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Elementary Excitations in Trapped BEC and Zero Mode Problem

D. L. Zhou·X. X. Yi·G. R. Jin·Y. H. Su·Y. X. Liu·C. P. Sun
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Abstract

We propose a natural expansion of the atomic field operator in studying elementary excitations in trapped Bose-Einstein Condensation (BEC) system near T=0K. Based on this expansion, a system of coupled equations for elementary excitations, which is equivalent to the standard linearized GP equation, is given to describe the collective excitation of BEC in a natual way. Applications of the new formalism to the homogeneous case emphasize on the zero mode and its relevant ground state of BEC.

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D. L. Zhou, X. X. Yi, G. R. Jin, Y. H. Su, Y. X. Liu, C. P. Sun. 2000-04-04. Elementary Excitations in Trapped BEC and Zero Mode Problem. https://arxiv.org/abs/quant-ph/0004012

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