Physical Review A

Center-of-mass motion in the many-body theory of Bose-Einstein condensates

Iwo Białynicki‐Birula, Zofia Białynicka-Birula

Published Jun 3, 2002• 33 citations

Abstract

The method of generating a family of new solutions starting from any wave function satisfying the nonlinear Schr\"odinger equation in a harmonic potential proposed recently [J. J. Garc\'{\i}a-Ripoll, V. M. P\'erez-Garc\'{\i}a, and V. Vekslerchik, Phys. Rev. E 64, 056602 (2001)] is extended to the many-body theory of mutually interacting particles. Our method is based on a generalization of the displacement operator known in quantum optics, and results in the separation of the center-of-mass motion from the internal dynamics of many-body systems. The center-of-mass motion is analyzed for an anisotropic rotating trap and a region of instability for intermediate rotational velocities is predicted.

DOI: 10.1103/physreva.65.063606

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