Theory of Interfacial Dzyaloshinskii-Moriya Interaction in Antiferromagnetic/Heavy-Metal Bilayers
Interfaces between antiferromagnets and heavy metals can induce Dzyaloshinskii-Moriya (DM) interactions. Knowledge of the DM parameters is essential for understanding and designing exotic spin structures, such as hedgehog skyrmions and chiral N\'eel walls, which are attractive for use in novel information storage technologies. We introduce a framework for computing the DM interaction in thin-film antiferromagnet/heavy-metal bilayers. In contrast to bilayers involving ferromagnets, in antiferromagnets with Rashba spin-orbit coupling, the DM interaction is not suppressed even at low temperatures. The material parameters control both the strength and sign of the interfacial DM interaction. Our results suggest a route toward controlling the DM interaction in antiferromagnetic materials by means of doping and electric fields.