Non-Hermitian skin effect induced by Rashba-Dresselhaus spin-orbit coupling

One-dimensional (1D) chains with nonreciprocal tunneling realizing the non-Hermitian skin effect (NHSE) have attracted considerable interest in the last years, whereas their experimental realization in real space remains limited to a few examples. In this Letter, we propose a generic way of implementing nonreciprocity based on a combination of Rashba-Dresselhauss spin-orbit coupling, existing for electrons, cold atoms, and photons, and a lifetime imbalance between two spin components. We show that one can realize the Hatano-Nelson model, the non-Hermitian Su-Schrieffer-Heeger model, and even observe the NHSE in a 1D potential well without the need for a lattice. We further demonstrate the practical feasibility of this proposal by considering the specific example of a photonic liquid-crystal microcavity. This platform allows one to switch on and off the NHSE by applying an external voltage to the microcavity.