A Novel 19$\sqrt {19} $ × 19$\sqrt {19} $ Superstructure in Epitaxially Grown 1T‐TaTe₂

Abstract

Abstract The spontaneous formation of electronic orders is a crucial element for understanding complex quantum states and engineering heterostructures in 2D materials. A novel × charge order in few‐layer‐thick 1T‐TaTe 2 transition metal dichalcogenide films grown by molecular beam epitaxy, which has not been realized, is report. The photoemission and scanning probe measurements demonstrate that monolayer 1T‐TaTe 2 exhibits a variety of metastable charge density wave orders, including the × superstructure, which can be selectively stabilized by controlling the post‐growth annealing temperature. Moreover, it is found that only the × order persists in 1T‐TaTe 2 films thicker than a monolayer, up to 8 layers. The findings identify the previously unrealized novel electronic order in a much‐studied transition metal dichalcogenide and provide a viable route to control it within the epitaxial growth process.