Ultrafast light-induced magnetization dynamics in ferromagnetic semiconductors

TL;DR

This paper develops a theoretical framework for understanding ultrafast light-induced magnetization dynamics in ferromagnetic semiconductors, highlighting the roles of carrier spin relaxation and optical excitation in controlling magnetization on femtosecond timescales.

Contribution

It introduces a novel theoretical approach using Lindblad semigroup methods to model nonlinear optical responses and magnetization control in ferromagnetic semiconductors under ultrafast excitation.

Findings

Demonstrates light-induced magnetization precession during femtosecond pulses

Shows the impact of hole-spin damping and polarization dephasing on magnetization dynamics

Reveals the interplay between optical excitation and spin interactions in controlling magnetization

Abstract

We develop a theory of the magnetization dynamics triggered by ultrafast optical excitation of ferromagnetic semiconductors. We describe the effects of the strong carrier spin relaxation on the nonlinear optical response by using the Lindblad semigroup method. We demonstrate magnetization control during femtosecond timescales via the interplay between circularly polarized optical excitation, hole-spin damping, polarization dephasing, and the Mn-hole spin interactions. Our results show a light-induced magnetization precession and relaxation for the duration of the optical pulse.