Effect of atom loss on collapse and revivals of phase coherence in small atomic samples

A small atomic sample at a single site of an optical lattice potential is a realization of an anharmonic oscillator with atomic collisions giving rise to the nonlinearity. Due to the atomic collisions, an initial state with a well-defined phase evolves into a complex superposition of states of different phase before returning to the initial state. In this realization, three-body loss (the dominant loss process at high densities) acts as a damping mechanism and decoheres the intermediate superpositions thus reducing the ability of the phase to revive at later times. For high densities the decoherence process is rapid and the system enters the classical regime where revivals do not occur.