Construction of monolayer IrTe2 and the structural transition under low temperatures**Project supported by the National Key Research & Development Project of China (Grant Nos. 2019YFA0308500, 2018YFA0305800, and 2016YFA0202300), the National Natural Science Foundation of China (Grant Nos. 51991340, 61888102, and 11888101), and the Chinese Academy of Sciences (Grant Nos. XDB28000000 and XDB30000000).

Abstract

Bulk iridium ditelluride (IrTe2) is a layered material and is known for its interesting electronic and structural properties, such as large spin–orbit coupling, charge ordering, and superconductivity. However, so far there is no experimental study about the fabrication of monolayer IrTe2. Here we report the formation of IrTe2 monolayer on Ir(111) substrate by direct tellurization method. Scanning tunneling microscope (STM) images show the coexistence of 1/5 phase and 1/6 phase structures of IrTe2 at room temperature. We also obtained STM images showing distorted stripe feature under low temperatures. This stripe feature is possibly induced by the strain between the IrTe2 monolayer and the metal substrate. Density functional theory (DFT) calculations show that the IrTe2 monolayer has strong interaction with the underlying Ir(111) substrate.