Quantum entanglement has attracted much attention in the study of quantum many-body systems because it plays important roles in various phenomena such as thermalization of isolated quantum systems. Especially, it is remarkable that the 2nd-order Renyi entropy (RE), which is a measure of entanglement, has been successfully measured in the system of bosons trapped in a 1D optical lattice.
$\quad$Motivated the experimental development, we study entanglement dynamics of bosons in a 1D optical lattice. Specifically, we calculate the time-evolution of the RE when the system is quenched from the deep Mott insulating (MI) regime. For quench within the MI regime, we derive the analytic expression for the time-evolution of RE and show that it oscillates with the period determined by the strength of the on-site interaction and finally converges to a certain value proportional to the subsystem size. On the other hand, for quench into the superfluid (SF) regime, RE does not oscillate but increases almost linearly and converges to a certain value that is also proportional to the subsystem size. We also show that the behavior of the 2nd-order RE exhibits distinct features depending of whether the system is quenched into the SF or MI phases. This implies that the signature of the SF-MI phase transition appears in the entanglement dynamics.
|Presenter name||Shion Yamashika|