Electron-Magnon Scattering in Magnetic Heterostructures Far Out-of-Equilibrium

TL;DR

This paper develops a theoretical framework for understanding ultrafast spin dynamics in magnetic heterostructures driven far from equilibrium, incorporating electron-magnon interactions and interface effects under laser excitation.

Contribution

It introduces a kinetic rate equation model for out-of-equilibrium electron-magnon scattering in magnetic heterostructures, extending existing interfacial spin phenomena to ultrafast laser-induced dynamics.

Findings

Describes spin dissipation via electron spin relaxation.

Extends interfacial spin effects to high-temperature, laser-driven regimes.

Provides a basis for understanding ultrafast spin manipulation in magnetic devices.

Abstract

We present a theory of out-of-equilibrium ultrafast spin dynamics in magnetic heterostructures based on the s-d model of ferromagnetism. Both in the bulk and across interfaces, the exchange processes between the itinerant s and the localized d electrons are described by kinetic rate equations for electron-magnon spin-flop scattering. The principal channel for dissipation of angular momentum is provided by spin relaxation of the itinerant electrons. Our theory extends interfacial spin phenomena such as torques, pumping, and the Peltier and Seebeck effects to address laser-induced rapid spin dynamics, in which the effective electron temperature may approach or even exceed the Curie temperature.