Uniaxial strain-induced phase transition in the 2D topological semimetal IrTe2

DOI: 10.1038/s43246-021-00130-5

Authors: Christopher W. Nicholson (University of Fribourg) , Maxime Rumo (University of Fribourg) , Aki Pulkkinen (University of Fribourg; LUT University) , Geoffroy Kremer (University of Fribourg) , Björn Salzmann (University of Fribourg) , Marie-Laure Mottas (University of Fribourg) , Baptiste Hildebrand (University of Fribourg) , Thomas Jaouen (University of Fribourg; Univ Rennes, CNRS, IPR (Institut de Physique de Rennes)—UMR 6251) , Timur K. Kim (Diamond Light Source) , Saumya Mukherjee (Diamond Light Source) , Keyuan Ma (University of Zurich) , Matthias Muntwiler (Paul-Scherrer-Institute) , Fabian O. Von Rohr (University of Zurich) , Cephise Cacho (Diamond Light Source) , Claude Monney (University of Zurich)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Communications Materials , VOL 2

State: Published (Approved)
Published: March 2021
Diamond Proposal Number(s): 24880

Abstract: Strain is ubiquitous in solid-state materials, but despite its fundamental importance and technological relevance, leveraging externally applied strain to gain control over material properties is still in its infancy. In particular, strain control over the diverse phase transitions and topological states in two-dimensional transition metal dichalcogenides remains an open challenge. Here, we exploit uniaxial strain to stabilize the long-debated structural ground state of the 2D topological semimetal IrTe2, which is hidden in unstrained samples. Combined angle-resolved photoemission spectroscopy and scanning tunneling microscopy data reveal the strain-stabilized phase has a 6 × 1 periodicity and undergoes a Lifshitz transition, granting unprecedented spectroscopic access to previously inaccessible type-II topological Dirac states that dominate the modified inter-layer hopping. Supported by density functional theory calculations, we show that strain induces an Ir to Te charge transfer resulting in strongly weakened inter-layer Te bonds and a reshaped energetic landscape favoring the 6×1 phase. Our results highlight the potential to exploit strain-engineered properties in layered materials, particularly in the context of tuning inter-layer behavior.

Journal Keywords: Electronic properties and materials; Surfaces, interfaces and thin films; Topological matter; Two-dimensional materials

Subject Areas: Materials, Physics


Instruments: I05-ARPES

Other Facilities: PEARL beamline at Swiss Light Source

Added On: 09/03/2021 08:15

Documents:
s43246-021-00130-5.pdf

Discipline Tags:

Surfaces Quantum Materials Hard condensed matter - electronic properties Physics Materials Science interfaces and thin films

Technical Tags:

Spectroscopy Angle Resolved Photoemission Spectroscopy (ARPES) X-ray Photoelectron Spectroscopy (XPS)