Atomic soliton in a traveling wave laser beam

Abstract

A vector quantum field theory is employed to study the propagation of an ultracold atomic wave packet in a traveling wave laser beam with a Gaussian intensity profile. The collective dipole-dipole correlation induced by photon exchanges between atoms produces a ‘‘Kerr-type’’ nonlinearity of atomic waves. We show that such an atomic nonlinearity could result in an atomic soliton under appropriate conditions.