Quantum transport properties of single-crystalline Ag2Se0.5Te0.5 nanowires as a new topological material

Abstract

We report a ternary silver chalcogenide, Ag₂Se_0.5Te_0.5, as a new topological material with improved quantum transport properties. Single-crystalline nanostructures of ternary silver chalcogenides Ag₂Se_xTe_1−x are synthesized with a tunable chemical composition via the chemical vapor transport method. Quantum transport studies reveal that Ag₂Se_0.5Te_0.5 nanowires present topological surface states with higher electron mobility and longer mean free path compared to binary Ag-chalcogenides. First-principles calculations also indicate that Ag₂Se_0.5Te_0.5 is a topological insulator, and the observed enhancement in transport properties could imply reduced bulk carrier contribution in the new ternary silver chalcogenide.