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

TL;DR

This paper investigates how spin-orbit coupling and Raman fields influence scattering in a one-dimensional Fermi gas, revealing resonances and threshold anomalies that depend on the dispersion regime, with implications for experimental control.

Contribution

It provides a detailed analysis of scattering resonances in a 1D Fermi gas with RD-SOC, highlighting the impact of different dispersion regimes and external fields on scattering behavior.

Findings

Strong scattering resonances near thresholds and quasi-bound states.

Distinct scattering behaviors between single-minimum and double-minimum dispersion regimes.

RD-SOC and Raman fields enable diverse 1D models in experiments.

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.