Imaging the surface electronic states in the family of magnetic topological EuM₂As₂

Gapping of Dirac surface states through time reversal symmetry breaking may realize the axion insulator state in condensed matter. Despite tremendous efforts, only few material systems fall into this category of intrinsic magnetic topological insulators. Recent theoretical calculations proposed the antiferromagnetic EuM₂X₂ family of materials to be topologically nontrivial magnetic insulator/semimetals. In this talk, I will present our recent findings on the surface electronic states in the family of EuM₂As₂ (M = In, Sn, Zn, Cd) using scanning tunneling microscopy and spectroscopy complemented with density-functional theory calculations.