Magneto Optic Kerr Effects of an Antiferromagnet - Topological Insulator Heterostructure*

We investigate the magneto-optic memory applications of a topological insulator proximity coupled to an anti-ferromagnet. We find that this gives rise to a high figure of merit magneto optic Kerr effects. The optical dielectric tensor elements are calculated using the Kubo formula and are based on a tight-binding electronic structure model. We calculate the Fermi level dependence of the MOKE signature and explore the AFM-TI optical phase diagram. This system can lead to applications such as a topologically protected high density antiferromagnetic magnetic optic memory device with ultra-low error rates.