Nonlinear Dynamics of Nuclear-Electronic Spin Processes in Ferromagnets

TL;DR

This paper investigates the nonlinear spin dynamics in ferromagnets with coupled electron and nuclear spins, revealing ultrafast coherent relaxation phenomena that could enhance material analysis and technological applications.

Contribution

It introduces the concept of ultrafast coherent relaxation in ferromagnetic spin systems with hyperfine interactions and circuit coupling, highlighting new relaxation behaviors.

Findings

Ultrafast coherent spin relaxation occurs several orders faster than T2.

Coupling with a resonance circuit influences spin relaxation dynamics.

Potential applications in material characterization and spin-based technologies.

Abstract

Spin dynamics is considered in ferromagnets consisting of electron and nuclear subsystems interacting with each other through hyperfine forces. In addition, the ferromagnetic sample is coupled with a resonance electric circuit. Under these conditions, spin relaxation from a strongly nonequilibrium initial state displays several peculiarities absent for the standard set-up in studying spin relaxation. The main feature of the nonlinear spin dynamics considered in this communication is the appearance of ultrafast coherent relaxation, with characteristic relaxation times several orders shorter than the transverse relaxation time $T_2$. This type of coherent spin relaxation can be used for extracting additional information on the intrinsic properties of ferromagnetic materials and also can be employed for different technical applications.