Momentum-dependent s-wave and d-wave interactions in atomic Bose-Einstein condensates

Abstract

We investigate the role of momentum-dependent interactions to determine the ground-state properties in the Bose-Einstein condensate for large scattering lengths (a) such that ka ≥1, even for small momentum (p) where p=ℏk and k is the wave number. The results for momentum-dependent and momentum-independent interactions differ significantly, even for moderate values of a, and the effect of higher partial-wave interaction increases with the increase in a. We have made an attempt to compare the theoretical column density with experimental results at different magnetic fields [Cornish et al., Phys. Rev. Lett. 85, 1795 (2000)]. Since the initial number of atoms changes while swapping the magnetic field and the actual value of the number of atoms at different magnetic fields is not known, we studied the dependence of column densities on the value of N at different magnetic fields. We present here the results for those values of N for which the theoretical column densities are comparable with the experimental results. It is shown that the column density for 85Rb atoms at 100 nK with momentum-dependent interaction is in fairly good agreement with the experimental values for different values of N at two different values of magnetic fields (B=157.2 and 156.4 G).