Evidence of multiple topological band structures in EuGa₂Al₂

The intermetallic compounds of the typical ThCr₂Si₂-structure type have uncovered a large family of material base exhibiting rich interplay of the lattice, magnetic, orbital and charge degrees of freedom, leading to a rich variety of states including antiferromagnetism, high temperature superconductivity, heavy fermion behavior, charge density wave (CDW), etc. EuGa₂Al₂ is such a rare-earth-based ThCr₂Si₂-structure type intermetallic with multiple magnetic transitions and CDW order. In this talk, a comprehensive electronic structure of EuGa₂Al₂ measured by angle-resolved photoemission spectroscopy will be presented. The existence of multiple topological bands will be elucidated with the combination of first-principles calculations. We will also discuss the effect of magnetism and CDW order on the electronic structures.