Surface weak ferromagnetism

Abstract

This paper proposes a model of a N\'{e}el-ordered antiferromagnet exhibiting a weak ferromagnetic moment restricted to the crystal surface, generated by spin-orbit coupling induced by broken surface symmetries. Depending on crystal termination, the surface magnetic moment can align with identical or opposing signs on the top and bottom surfaces, resulting in a zero Faraday effect paired with a finite Kerr effect upon reflection for the latter configuration.