Spin-charge filtering through a spin-orbit coupled quantum dot controlled via an Aharonov-Bohm interferometer

Abstract

We show that a strongly correlated quantum dot embedded in an Aharonov-Bohm interferometer can be used to filter both charge and spin at zero voltage bias. The magnitude with which the Aharonov-Bohm arm is coupled to the system controls the many-body effects on the quantum dot. When the quantum dot is in the Kondo regime, the flow of charge through the system can be tuned by the phase of the Aharonov-Bohm arm, ${\ensuremath{\varphi}}_{\mathit{AB}}$. Furthermore, when a spin-orbit interaction is present on a Kondo quantum dot, we can control the flow of spin by the spin-orbit phase, ${\ensuremath{\varphi}}_{\mathit{SO}}$. The existence of the Kondo peak at the Fermi energy makes it possible to control the flow of both charge and spin in the zero voltage bias limit.