Scientific article
OA Policy
English

Insensitivity of the striped charge orders in IrTe2 to alkali surface doping implies their structural origin

Published inPhysical review materials, vol. 5, no. 7, 074002
Publication date2021-07-02
First online date2021-07-02
Abstract

We present a combined angle-resolved photoemission spectroscopy and low-energy electron diffraction (LEED) study of the prominent transition metal dichalcogenide IrTe2 upon potassium (K) deposition on its surface. Pristine IrTe2 undergoes a series of charge-ordered phase transitions below room temperature that are characterized by the formation of stripes of Ir dimers of different periodicities. Supported by density functional theory calculations, we first show that the K atoms dope the topmost IrTe2 layer with electrons, therefore strongly decreasing the work function and shifting only the electronic surface states towards higher binding energy. We then follow the evolution of its electronic structure as a function of temperature across the charge-ordered phase transitions and observe that their critical temperatures are unchanged for K coverages of 0.13 and 0.21 monolayer. Using LEED we also confirm that the periodicity of the related stripe phases is unaffected by the K doping. We surmise that the charge-ordered phase transitions of IrTe2 are robust against electron surface doping, because of its metallic nature at all temperatures, and due to the importance of structural effects in stabilizing charge order in IrTe2.

Keywords
  • Phase diagrams
  • Phase transitions
  • Surface states
  • Dichalcogenides
  • Angle-resolved photoemission spectroscopy
  • Density functional theory
  • Low-energy electron diffraction
  • Scanning tunneling microscopy
Affiliation entities Not a UNIGE publication
Research groups
Citation (ISO format)
RUMO, M. et al. Insensitivity of the striped charge orders in IrTe2 to alkali surface doping implies their structural origin. In: Physical review materials, 2021, vol. 5, n° 7, p. 074002. doi: 10.1103/PhysRevMaterials.5.074002
Main files (1)
Article (Published version)
accessLevelPublic
Identifiers
Journal ISSN2475-9953
229views
157downloads

Technical informations

Creation07/12/2022 9:21:00 AM
First validation07/12/2022 9:21:00 AM
Update time03/16/2023 7:02:55 AM
Status update03/16/2023 7:02:54 AM
Last indexation11/01/2024 2:18:06 AM
All rights reserved by Archive ouverte UNIGE and the University of GenevaunigeBlack