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arXiv · 1702.04714

Bosons with incommensurate potential and spin-orbit coupling

Sayak Ray·Bhaskar Mukherjee·S. Sinha·K. Sengupta
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Abstract

We chart out the phase diagram of ultracold `spin-half' bosons in a one-dimensional optical lattice in the presence of Aubry-Andr\'e (AA) potential and with spin-orbit (SO) and Raman couplings investigating the transition from superfluid (SF) to localized phases and the existence of density wave phase for nearest-neighbor interaction (NNI). We show that the presence of SO coupling and AA potential leads to a novel spin-split momentum distribution of the bosons in the localized phase near the boundary with the SF phase, which can act as a signature of such a transition. We also obtain the level statistics of the bosons in the superfluid phase with finite NNI and demonstrate its change from Gaussian Unitary Ensemble (GUE) to Gaussian Orthogonal Ensemble (GOE) as a function of the Raman coupling. We discuss experiments which can test our theory.

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Sayak Ray, Bhaskar Mukherjee, S. Sinha, K. Sengupta. 2017-02-15. Bosons with incommensurate potential and spin-orbit coupling. https://doi.org/10.1103/physreva.96.023607

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