Dissipationless Spin-Charge Conversion in Excitonic Pseudospin Superfluid

TL;DR

This paper introduces a novel dissipationless spin-charge conversion mechanism using an excitonic pseudospin superfluid in electron-hole double layers, enabling efficient spintronics without energy loss.

Contribution

It proposes a new dissipationless spin-charge conversion mechanism based on excitonic superfluidity, derived from a coupled quantum-dot model.

Findings

Demonstrates spin-charge coupled Josephson equations for excitonic superflow.

Shows magnetic fields lift exciton degeneracy, enabling superfluidity.

Predicts dissipationless spin-charge conversion in double layer systems.

Abstract

Spin-charge conversion by inverse spin Hall effect or inverse Rashba-Edelstein effect is prevalent in spintronics but dissipative. We propose a dissipationless spin-charge conversion mechanism by an excitonic pseudospin superfluid in an electron-hole double layer system. Magnetic exchange fields lift singlet-triplet degeneracy of interlayer exciton levels in the double layer system. Condensation of the singlet-triplet hybridized excitons breaks both a U(1) gauge symmetry and a pseudospin rotational symmetry around the fields, leading to spin-charge coupled superflow in the system. We demonstrate the mechanism by deriving spin-charge coupled Josephson equations for the excitonic superflow from a coupled quantum-dot model.