SUltrafast 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.

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