arXiv:2111.11054 · Physical Review A

Particle and spin transports of spin-orbit-coupled Fermi gases through a quantum point contact

Xiaoyu Dai, Boyang Liu

Published Apr 21, 2022• 3 citations

Abstract

The particle and spin transports through a quantum point contact between two Fermi gases with Raman-induced spin-orbit coupling are investigated. We show that the particle and spin conductances both demonstrate the structure of plateaus due to the mesoscopic scale of the quantum point contact. Compared with that of normal Fermi gases, the height of the plateau of the particle conductance is enhanced by the spin-orbit-coupling effect for the whole parameter space. This implies that the 0.7 anomaly observed in mesoscopic experiments is unlikely to be induced purely by the spin-orbit coupling. Furthermore, the generation of spin current is investigated in this system. We find that the spin current can be induced by only the bias of the spin difference between the two reservoirs for the case of vanishing two-photon detuning. When the two-photon detuning is nonzero, the spin current can also be generated by the bias of the total particle number between the two reservoirs.

DOI: 10.1103/physreva.105.043313

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