Protection of a non-Fermi liquid by spin-orbit interaction

Abstract

We show that a thermoelectric transport through a Quantum Dot (QD) - single-mode Quantum Point Contact (QPC) nano-device demonstrating pronounced fingerprints of Non-Fermi Liquid (NFL) behavior in the absence of external magnetic field is protected from magnetic field NFL destruction by strong spin-orbit interaction (SOI). The mechanism of protection is associated with appearance of additional scattering processes due to lack of spin conservation in the presence of both SOI and small Zeemann field. The interplay between in-plane magnetic field $\vec B$ and SOI is controlled by the angle between $\vec B$ and $\vec B_{SOI}$ We predict strong dependence of the thermoelectric coefficients on the orientation of the magnetic field and discuss a window of parameters for experimental observation of NFL effects.