arXiv:cond-mat/0210258 · Physical Review A

Bogoliubov theory of a Bose-Einstein condensate in the particle representation

Jacek Dziarmaga, Krzysztof Sacha

Published Mar 26, 2003• 20 citations

Abstract

In the number-conserving Bogoliubov theory of the Bose-Einstein condensate, the Bogoliubov transformation between quasiparticles and particles is nonlinear. We invert this nonlinear transformation and give a general expression for eigenstates of the Bogoliubov Hamiltonian in particle representation. The particle representation unveils the structure of a condensate multiparticle wave function. We give several examples to illustrate a general formalism.

DOI: 10.1103/physreva.67.033608

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