Spin pumping into quantum spin nematic states

TL;DR

This paper presents a theoretical analysis of spin pumping into spin-nematic states, revealing how interfacial exchange coupling affects Gilbert damping and how spin pumping depends on frequency, magnetic field, and interface type.

Contribution

It introduces a mean-field theoretical framework using Schwinger bosons to analyze spin pumping into spin-nematic states, highlighting the distinct roles of two Schwinger bosons.

Findings

Spin pumping is influenced by interfacial exchange coupling.

Two Schwinger bosons contribute differently to spin pumping.

Spin pumping depends on resonant frequency, magnetic field, and interface type.

Abstract

We theoretically study spin pumping into a spin-nematic state in a junction system composed of a ferromagnetic insulator and a spin-nematic insulator, described by using the spin-1 bilinear-biquadratic model. We analyze an increase of the Gilbert damping in ferromagnetic resonance (FMR) due to an interfacial exchange coupling within a mean-field theory based on the Schwinger boson method. We find that the two Schwinger bosons contribute in distinct ways to spin pumping. We report a detailed dependence of the spin pumping on a resonant frequency, a magnetic field, and an interface type.