Topologically protected surface states in TaPdTe5

By combining angle-resolved photoemission spectroscopy (ARPES) and first-principles calculations, we have studied the electronic band structure of a topological material candidate TaPdTe5.Two inverted bulk gaps determined through the parity analysis were observed in TaPdTe5 near the Fermi level, which causes the appearance of topologically protected surface states on the (010) surface. Beside the surface state, we also observed strong surface resonance state. The hybridization between the surface resonance state and the surface state changes the quasi-one-dimensional like Fermi surface sheets of the surface resonance state into two-dimensional Fermi pockets. Our findings provide comprehensive understanding about the interesting surface states in TaPdTe5.