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arXiv · 1501.01362

Superfluidity of pure spin current in ultracold Bose gases

Qizhong Zhu·Qing-feng Sun·Biao Wu
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Abstract

We study the superfluidity of a pure spin current that is a spin current without mass current. We examine two types of pure spin currents, planar and circular, in spin-1 Bose gas. For the planar current, it is usually unstable, but can be stabilized by the quadratic Zeeman effect. The circular current can be generated with spin-orbit coupling. When the spin-orbit coupling strength is weak, we find that the circular pure spin current is the ground state of the system and thus a super-flow. We discuss the experimental schemes to realize and detect a pure spin current.

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Qizhong Zhu, Qing-feng Sun, Biao Wu. 2015-01-07. Superfluidity of pure spin current in ultracold Bose gases. https://doi.org/10.1103/physreva.91.023633

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