Controllable spin entanglement production in a quantum spin Hall ring

TL;DR

This paper demonstrates how to electrically control spin entanglement in a quantum spin Hall ring by manipulating dynamical phases through gate potential and Rashba interaction, enabling tunable entanglement generation.

Contribution

It introduces a novel setup for controllable spin entanglement production in a quantum spin Hall ring using phase-dependent mechanisms.

Findings

Entanglement depends on dynamical phases in the edge states.

Electrical control of entanglement via gate potential and Rashba interaction.

Postselection of detector events reveals measurable entanglement.

Abstract

We study the entanglement production in a quantum spin Hall ring geometry where electrons of opposite spins are emitted in pairs from a source and collected in two different detectors. Postselection of coincidence detector events gives rise to entanglement in the system, measurable through correlations between the outcomes in the detectors. We have chosen a geometry such that the entanglement depends on the dynamical phases picked up by the edge states as they move around the ring. In turn, the dependence of the phases on gate potential and Rashba interaction allows for a precise electrical control of the entanglement production in the ring.