Electric dipole moment as descriptor for interfacial Dzyaloshinskii-Moriya interaction
Hongying Jia, Bernd Zimmermann, Gregor Michalicek, Gustav Bihlmayer, Stefan Blügel
Abstract
Chiral magnets are of fundamental interest and have important technological ramifications. The origin of chiral magnets lies in the Dzyaloshinskii-Moriya interaction (DMI), an interaction whose experimental and theoretical determination is laborious. We derive an expression that identifies the electric dipole moment as descriptor for the systematic design of chiral magnetic multilayers. Using density functional theory calculations, we determine the DMI of (111)-oriented metallic ferromagnetic $Z/\mathrm{Co}/\mathrm{Pt}$ multilayers of ultrathin films. The nonmagnetic layer $Z$ determines the DMI at the Co-Pt interface. The results validate the electric and magnetic dipole moments as excellent descriptors. We found a linear relation between the electric dipole moment of Pt, the Allen electronegativity of $Z$, and the contribution of Pt to the total DMI.