Persistent spin currents in a quantum ring with multiple arms in the presence of spin-orbit interaction

Abstract

We study theoretically the transmission coefficients and the persistent spin currents in a quantum ring with multiple arms in the presence of spin-orbit interaction. One-dimensional quantum waveguide theory is developed and applied to triple-arm open Aharonov-Bohm rings. It is found that the persistent spin currents can be induced by the spin-orbit coupling which stems from a nonsymmetrical confined potential in a mesoscopic ring. It is also found that the spin-orbit coupling can increase or decrease the total persistent currents, and the directions of the persistent spin currents depend on the intensity of spin-orbit coupling. The obtained results further confirm that the effective flux induced by the spin-orbit interaction exerts important effects on the transmission coefficients and the persistent spin currents in a quantum ring.