BEHAVIOUR OF A BOSE-EINSTEIN CONDENSATE NEAR THE ZERO DISPERSION POINT
Pages 72-78
Anca Visinescu, Dan Grecu
Abstract
A cigar shaped BEC in a periodic external field is analyzed using the multiple scales method. Usually the dominant amplitude satisfies the completely integrable NLS equation. The discussion is extended to the vicinity of the "zero-dispersion point" (the point where the coefficient of the second order derivative vanishes). The multiple scales method is adapted to this situation and an equation containing the third order derivative is found for the dominant amplitude. It is no more integrable and several properties of it are investigated.