Chiral-mediated entanglement in an Aharonov-Bohm ring

Abstract

We study the orbital entanglement in a biased Aharonov-Bohm ring connected in a four-terminal setup. We find that the concurrence achieves a maximum when the magnetic flux ${\ensuremath{\Phi}}_{B}$ coincides with an integer number of a half flux quantum ${\ensuremath{\Phi}}_{0}/2$. We show that this behavior is a consequence of the existence of degenerate states of the ring having opposite chirality. We also analyze the behavior of the noise as a function of $\ensuremath{\Phi}$ and discuss the reliability of this quantity as evidence of entanglement.