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Excitation Spectra of Mott-insulator Phases of ~7Li Atoms in an Optical Lattice

Yongmei Zhang

Published Jan 1, 2009• 0 citations

Abstract

In this paper,the excitation spectra of quasiparticles and quasiholes in Mott-insulator phase of 7Li atoms which have an attractive two-body interaction in an optical lattice are discussed when the repulsive three-body interaction is considered.It is concluded that with the increase of the repulsive three-body interaction,the energy of quasiparticles is increased and the energy of quasiholes is decreased. For a low filling factor of atoms,the energy of quasiholes is decreased slightly.With the increase of the filling factor of atoms,the energy of quasiholes is decreased remarkably.

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