X-ray View of Light-Induced Spin Reorientation in TmFeO$_{3}$: Direct Observation of a 90$^\circ$ N\'eel Vector Rotation

TL;DR

This study uses time-resolved X-ray magnetic linear dichroism to directly observe ultrafast 90-degree spin reorientation of the Neel vector in TmFeO, demonstrating a method to probe antiferromagnetic dynamics on picosecond timescales.

Contribution

It provides the first direct observation of ultrafast Neel vector reorientation in TmFeO using reflection geometry, advancing understanding of antiferromagnetic spin dynamics.

Findings

Neel vector undergoes a 90b0 rotation within 20 ps

Spin reorientation occurs mainly within the a-c plane

Method enables ultrafast probing of antiferromagnetic dynamics

Abstract

Using time-resolved X-ray magnetic linear dichroism in reflection, we provide a direct probe of the N\'eel vector dynamics in TmFeO$_3$ on a ultrafast timescale. Our measurements reveal that, following optical excitation, the N\'eel vector undergoes a spin reorientation transition primarily within the a-c plane, completing a full 90{\deg} rotation within approximately 20 ps. This study highlights the ability to probe dynamics of antiferromagnets at its intrinsic timescale in reflection geometry, paving the way for investigations of a wide range of antiferromagnets grown on application relevant substrates.