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arXiv · 2010.04374

Application of the inhomogeneous Kibble-Zurek mechanism to quench dynamics in the transition from a Mott-insulator to a superfluid in a finite system

Abstract

We apply the theory of inhomogeneous Kibble-Zurek mechanism to understand quench dynamics from the Mott insulator to the superfluid in a cold Bose gases confined in both a two-dimensional optical lattice and a harmonic trap. The local quench time and the freeze-out region associated with the nonadiabatic transition take a nontrivial positional dependence due to the Mott-lobe structure of the ground state phase diagram of the Bose-Hubbard model. We demonstrate that the quench dynamics through the time-dependent Gutzwiller simulations, revealing inhomogeneous properties of the growth of the superfluid order parameter. The inhomogeneous Kibble-Zurek theory is applicable for the shallow harmonic trap.

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Yoshihiro Machida, Kenichi Kasamatsu. 2021-01-12. Application of the inhomogeneous Kibble-Zurek mechanism to quench dynamics in the transition from a Mott-insulator to a superfluid in a finite system. https://doi.org/10.1103/physreva.103.013310

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