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arXiv · 1204.1887

Spin-Orbit Coupled Degenerate Fermi Gases

Abstract

Spin-orbit coupling plays an increasingly important role in the modern condensed matter physics. For instance, it gives birth to topological insulators and topological superconductors. Quantum simulation of spin-orbit coupling using ultracold Fermi gases will offer opportunities to study these new phenomena in a more controllable setting. Here we report the first experimental study of a spin-orbit coupled Fermi gas. We observe spin dephasing in spin dynamics and momentum distribution asymmetry in the equilibrium state as hallmarks of spin-orbit coupling. We also observe evidences of Lifshitz transition where the topology of Fermi surfaces change. This serves as an important first step toward finding Majorana fermions in this system.

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Pengjun Wang, Zeng-Qiang Yu, Zhengkun Fu, Jiao Miao, Lianghui Huang, Shijie Chai, Hui Zhai, Jing Zhang. 2012-04-09. Spin-Orbit Coupled Degenerate Fermi Gases. https://doi.org/10.1103/physrevlett.109.095301

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