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arXiv · 1409.3149

Approach for making visible and stable stripes in a spin-orbit-coupled Bose-Einstein superfluid

Abstract

The striped phase exhibited by a spin-$1/2$ Bose-Einstein condensate with spin-orbit coupling is characterized by the spontaneous breaking of two continuous symmetries: gauge and translational symmetry. This is a peculiar feature of supersolids and is the consequence of interaction effects. We propose an approach to produce striped configurations with high-contrast fringes, making their experimental detection in atomic gases a realistic perspective. Our approach, whose efficiency is directly confirmed by three-dimensional Gross-Pitaevskii simulations, is based on the space separation of the two spin components into a two-dimensional bilayer configuration, causing the reduction of the effective interspecies interaction and the increase of the stability of the striped phase. We also explore the effect of a $π/2$ Bragg pulse, causing the increase of the fringe wavelength, and of a $π/2$ rf pulse, revealing the coherent nature of the order parameter in the spin channel.

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Giovanni I. Martone, Yun Li, Sandro Stringari. 2014-12-02. Approach for making visible and stable stripes in a spin-orbit-coupled Bose-Einstein superfluid. https://doi.org/10.1103/physreva.90.041604

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