Work

Quantum-Confined Lifshitz Transition on Weyl Semimetal Td-MoTe2

Year: 2024

Type: article

Abstract: High Resolution Image Download MS PowerPoint Slide Adsorption of alkali atoms onto material surfaces is widely utilized for controlling electronic properties and is particularly effective for two-dimensional materials. While tuning the chemical potential and band gap and creating quantum-confined states are well established for alkali adsorption on semiconductors, the effects on semimetallic systems remain largely elusive. Here, utilizing angle-resolved photoemission spectroscopy measurements and density functional theory calculations, we disclose the creation of two-dimensional electron gas and the quantum-confined Lifshitz transition at the surface of a Weyl semimetal T d -MoTe 2 by potassium adsorption. Electrons from potassium adatoms are shown to be transferred mainly to the lowest unoccupied band within the gapped part of the Brillouin zone, which, in turn, induces strong surface band bending and quantum confinement in the topmost layer. The quantum-confined topmost layer evolves from a semimetal to a strong metal with a Lifshitz transition departing substantially from the bulk band. The present finding and its underlying mechanism can be exploited for the creation of electronic heterojunctions in van der Waals semimetals.

Source: ACS Nano

DOI: 10.1021/acsnano.4c05726

Authors: Hyunjin Jung, Kyung-Hwan Jin, Minki Sung, Jimin Kim, Jaeyoung Kim, Han Woong Yeom

Institutions: Pohang University of Science and Technology, Institute for Basic Science, Jeonbuk National University

Language: English

Topic: 2D Materials and Applications

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,500

Funders: U.S. Department of Energy, Pohang University of Science and Technology, Institute for Basic Science, Jeonbuk National University