Laser-enhanced magnetism in SmFeO$_3$

TL;DR

This paper investigates how laser-driven phonons can enhance magnetic interactions in SmFeO$_3$, revealing phase transitions and methods to control magnetic properties for spintronic applications.

Contribution

It introduces a simulation of spin dynamics coupled to laser-driven phonons, identifying conditions for phase transitions and methods to enhance magnetic interactions.

Findings

Linear coupling leads to a magnetophononic phase transition.

Quadratic coupling does not induce a phase transition.

Chirp protocols can control phase transitions and magnetic enhancement.

Abstract

To coherently enhance inherent weak magnetic interactions in rare-earth orthoferrite SmFeO$_3$ as a functional material for spintronic applications, we simulate the dissipative spin dynamics that are linearly and quadratically coupled to laser-driven infrared-active phonons. When linear coupling dominates, we discover a magnetophononic dynamical first-order phase transition in the nonequilibrium steady state which can inhibit strong enhancement of magnetic interactions. By contrast, when quadratic spin-phonon coupling dominates, no phase transition exists at experimentally relevant parameters. By utilizing a chirp protocol, the phase transition can be engineered, enabling stronger magnetic interactions. We also discuss the route for experimental observation of our results.