Altermagnetism in MnTe: Origin, predicted manifestations, and routes to detwinning

MnTe has recently attracted attention as an altermagnetic candidate. Experimentally it order of ferromagnetic $ab$ planes, stacked antiferromagnetically along $c$. We show that this magnetic (by itself nontrivial, since the in-plane exchange in antiferromagnetic) opens intriguing possibility manufacturing altermagnetically detwinned samples and generate observable magneto-optical response (which we calculate from first principles) a signature altermagnetism.