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Journal of the Physical Society of Japan

Collective Excitations of Trapped Bose–Fermi Mixture of Atomic Gases in RPA

Takaaki Sogo, Takahiko Miyakawa, T. Suzuki, Hiroyuki Yabu

Published Jan 1, 2003• 0 citations
Publisher

Abstract

Collective excitations of a trapped Bose–Fermi mixture of atomic gases are studied in a random-phase approximation. Density profiles in the ground states are solved in the mean field approximation for various strengths of Bose–Fermi interaction. Monopole strength distributions and the dynamical structure factors are investigated for two types of the Bose–Fermi mixture. It is found in the mixture with the large excess of bosons the fermionic strength is concentrated in a single collective state for strong Bose–Fermi interactions. The dynamical structure factors for these collective states show that fermions are correlated through the Bose condensate. Time dependent behavior of the system after an external impulse is also studied.

DOI
10.1143/jpsjs.72sc.144

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