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arXiv · 1610.00190

Spin-orbit-induced resonances and threshold anomalies in a reduced dimension Fermi gas

Su-Ju Wang·Chris H. Greene
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Abstract

We calculate the reflection and transmission probabilities in a one-dimensional Fermi gas with an equal mixing of the Rashba and Dresselhaus spin-orbit coupling (RD-SOC) produced by an external Raman laser field. These probabilities are computed over multiple relevant energy ranges within the pseudo-potential approximation. Strong scattering resonances are found whenever the incident energy approaches either a scattering threshold or a quasi-bound state attached to one of the energetically closed higher dispersion branches. A striking difference is demonstrated between two very different regimes set by the Raman laser intensity, namely between scattering for the single- minimum dispersion versus the double-minimum dispersion at the lowest threshold. The presence of RD-SOC together with the Raman field fundamentally changes the scattering behavior and enables the realization of very different one-dimensional theoretical models in a single experimental setup when combined with a confinement-induced resonance.

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Su-Ju Wang, Chris H. Greene. 2016-10-29. Spin-orbit-induced resonances and threshold anomalies in a reduced dimension Fermi gas. https://doi.org/10.1103/physreva.94.053635

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