A ring of BEC pools as a trap for persistent flow

Jacek Dziarmaga; Marek Tylutki; Wojciech H. Zurek

doi:10.1103/physrevb.84.094528

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arXiv · 1103.0669

A ring of BEC pools as a trap for persistent flow

Jacek Dziarmaga·Marek Tylutki·Wojciech H. Zurek

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Abstract

Mott insulator - superfluid transition in a periodic lattice of Josephson junctions can be driven by tunneling rate increase. Resulting winding numbers $W$ of the condensate wavefunction decrease with increasing quench time in accord with the Kibble-Zurek mechanism (KZM). However, in very slow quenches Bose-Hubbard dynamics rearranges wavefunction phase so that its random walk cools, $\bar{W^2}$ decreases and eventually the wavefunction becomes too cold to overcome potential barriers separating different $W$. Thus, in contrast with KZM, in very slow quenches $\bar{W^2}$ is set by random walk with "critical" step size, independently of $\tau_Q$.

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Jacek Dziarmaga, Marek Tylutki, Wojciech H. Zurek. 2011-03-03. A ring of BEC pools as a trap for persistent flow. https://doi.org/10.1103/physrevb.84.094528

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