On Thursday February 01th 2024, we have the pleasure to welcome in SPINTEC Oksana Chubykalo-Fesenko from Instituto de Ciencia de Materiales de Madrid, CSIC, Spain. She will give us a seminar at 11:00 entitled :
Ultrafast manipulation of antiferromagnetic Order and domain wall dynamics by novel laser induced torques
Place : IRIG/SPINTEC, auditorium 445 CEA Building 10.05 (access to CEA requires an entry authorization. Request it before January 20th at admin.spintec@cea.fr)
video conference : https://grenoble-inp.zoom.us/j/96937823317
Code secret: 981948
Abstract : Ultrafast manipulation of the Néel vector in antiferromagnets most commonly occurs by generation of spin-orbit (SOT) or spin-transfer (STT) torques. Here, by means of atomistic spin dynamics simulations, we predict another possibility for antiferromagnetic domain switching by using novel laser optical torques (LOTs) in Mn2Au. The driving mechanism takes advantage of the sizeable exchange enhancement, characteristic of antiferromagnetic dynamics, allowing for picosecond 90 and 180-degree precessional toggle switching of the Néel vector. We demonstrate the opportunity for LOTs to produce deterministic, non-toggle switching of single antiferromagnetic domains by using a combination of different laser pulses. Interestingly, LOT can efficiently drive 90◦ domain walls (DWs) but their spatial symmetry forbids the motion of 180◦ walls. In the steady-state regime, DW kinematics displays special relativity signatures accessed for low laser intensities.