Rigorous mean-field dynamics of lattice bosons: Quenches from the Mott insulator

Institute for Theoretical Physics, University of Amsterdam - 1090 GL Amsterdam, The Netherlands, EU

^a m.snoek@uva.nl

Received: 12 April 2011
Accepted: 22 June 2011

Abstract

We provide a rigorous derivation of Gutzwiller mean-field dynamics for lattice bosons, showing that it is exact on fully connected lattices. We apply this formalism to quenches in the interaction parameter from the Mott insulator to the superfluid state. Although within mean-field the Mott insulator is a steady state, we show that a dynamical critical interaction U_d exists, such that for final interaction parameter U_f>U_d the Mott insulator is exponentially unstable towards emerging long-range superfluid order, whereas for U_f<U_d the Mott insulating state is stable. We discuss the implications of this prediction for finite-dimensional systems.