arXiv:1801.08959 · Physical Review A

Stabilization of nonlinear lattices: A route to superfluidity and hysteresis

Gentaro Watanabe A, Yongping Zhang

Published Jul 24, 2018• 5 citations

Abstract

The Bloch states of Bose-Einstein condensates (BECs) in pure nonlinear lattices (NLs) are dynamically unstable so that they cannot show superfluidity. We overcome this problem by finding that the two-component BECs in NLs can be stabilized by coherent linear coupling. Furthermore, in the limit of strong coherent coupling, the lowest Bloch band in the whole Brillouin zone can be dynamically stable. We also find a hysteretic behavior with looplike structure in the Bloch band resembling the so-called ``swallowtail'' loop. The dynamical stabilization and the looplike band structure can be realized in experiments by current technology. Our results are obtained from a discrete model, and major results are also confirmed by a continuum model.

DOI: 10.1103/physreva.98.013625

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