Excitation spectrum and electrical properties of the condensate of Bose atoms

Arnold M. Kosevich, B. I. Verkin

Published Jan 1, 2005• 0 citations

Abstract

It is shown that the condensate of a degenerated Bose gas consisting \nof neutral atoms possesses electrical properties which differ from a trivial \npolarization of the atoms in the electric field. A notion of an isotropic \nquadrupole moment (IQM) of a neutral atom is introduced. A distribution \nof IQM reflects a specific spatial ordering in the condensate and produces \na distribution of the electric potential. Small vibrations of the Bose gas are \nconsidered and a correction to the Bogoliubov spectrum of elementary excitations \nin the degenerated Bose gas is obtained. An additional term in \nthe Gross-Pitaevskii equation which is responsible for such a correction is \nfound and a new type of the nonlinear Schrodinger equation (NSE) is constructed. Since the Bose condensate is akin to the superfluid component \nin He II, a manifestation of its electrical activity could have a relation to the \nelectrical activity of the superfluid liquid observed experimentally.

DOI: 10.5488/cmp.8.4.773

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