Superfluid Spin Transistor

TL;DR

This paper introduces a superfluid spin transistor that utilizes the Hall response of topological defects in 2D magnetic insulators to identify the BKT transition, enabling control of spin and vorticity currents.

Contribution

It proposes a novel superfluid spin transistor design based on topological defect responses to detect the BKT transition in 2D magnetic insulators.

Findings

Transition from spin superfluidity to normal spin transport observed.

Universal jump in spin stiffness at BKT transition.

Modulation of spin and vorticity currents via tuning magnetic parameters.

Abstract

We propose to use the Hall response of topological defects, such as merons and antimerons, to spin currents in 2D magnetic insulator with in-plane anisotropy for identification of the Berezinskii-Kosterlitz-Thouless (BKT) transition in a transistor-like geometry. Our numerical results relying on a combination of Monte Carlo and spin dynamics simulations show transition from spin superfluidity to conventional spin transport, accompanied by the universal jump of the spin stiffness and exponential growth of the transverse vorticity current. We propose a superfluid spin transistor in which the spin and vorticity currents are modulated by tuning the in-plane magnet across BKT transition, e.g., by changing the exchange interaction, magnetic anisotropy, or temperature.