Theoretically predicted picosecond optical switching of spin chirality in multiferroics

TL;DR

This paper presents a theoretical model showing that picosecond terahertz optical pulses can switch spin chirality states in multiferroic Mn perovskites by exciting electromagnons, enabling controlled manipulation of spin spirals.

Contribution

It introduces a detailed theoretical framework demonstrating all-optical control of spin chirality in multiferroics via electromagnon excitation.

Findings

Optical pulses can switch spin chirality states.

Four distinct spin spiral states are controllable.

Dynamical pattern formation occurs during switching.

Abstract

We show theoretically with an accurate spin Hamiltonian describing the multiferroic Mn perovskites that the application of the picosecond optical pulse with a terahertz frequency can switch the spin chirality through intensely exciting the electromagnons. There are four states with different spin chiralities, i.e. clockwise and counterclockwise ab/bc-plane spin spirals, and by tuning the strength, shape and length of the pulse, the switching among these states can be controlled at will. Dynamical pattern formation during the switching is also discussed.