Quantum dynamics of instability-induced pulsations of a Bose-Einstein condensate in an optical lattice

Description/Abstract

We study quantum dynamics of a Bose-Einstein condensate in a one-dimensional optical lattice in the limit of weak atom-atom interactions within the truncated Wigner approximation for a system with one dynamically
unstable mode. This extends previous classical studies of a pulsating dynamical instability in which atoms
periodically collect together and subsequently disperse back into the initial homogeneous state. We observe
that the quasiperiodic behavior still persists in the presence of quantum fluctuations for a single realization that represents a typical experimental outcome, but ensemble averages show various manifestations of quantum statistics. Quantum effects become more prominent when the effective interaction strength is increased.