Manipulation of Ferromagnets via the Spin-Selective Optical Stark Effect

TL;DR

This paper presents a theoretical study of how polarized light can manipulate magnetization in dilute magnetic semiconductors through the spin-selective optical Stark effect, enabling effective magnetic field induction.

Contribution

It introduces a theoretical model linking the inverse Faraday effect to the spin-selective optical Stark effect in magnetic semiconductors, highlighting a new mechanism for optical magnetization control.

Findings

Strong laser pulses induce effective magnetic fields of several teslas.

Polarized light facilitates angular momentum transfer between lattice and magnetization.

Theoretical demonstration of optical control of magnetization in (Ga,Mn)As.

Abstract

We investigate the non-resonant all-optical switching of magnetization. We treat the inverse Faraday effect (IFE) theoretically in terms of the spin-selective optical Stark effect for linearly or circularly polarized light. In the dilute magnetic semiconductors (Ga,Mn)As, strong laser pulses below the band gap induce effective magnetic fields of several teslas in a direction which depends on the magnetization and light wave vectors. Our theory demonstrates that the polarized light catalyzes the angular momentum transfer between lattice and the magnetization.