Band hybridization at the semimetal-semiconductor transition of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>Ta</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi>NiSe</mml:mi><mml:mn>5</mml:mn></mml:msub></mml:mrow></mml:math> enabled by mirror-symmetry breaking
Matthew D. Watson, Igor Marković, Edgar Abarca Morales, Patrick Le Fèvre, Michael Merz, Amir A. Haghighirad, Philip D. C. King
Abstract
This paper presents a Ta2NiSe5 semimetal-semiconductor transition using ARPES and show hybridized bands and a spectral gap at low temperatures. The energy scales involved, however, are comparable to those found in DFT calculations incorporating the known orthorhombic-monoclinic phase transition that accompanies the transition, indicating an important role for these symmetry-breaking structural distortions, which are always present in candidate exciton insulator materials more generally.
Topics & Concepts
ExcitonPhase transitionCondensed matter physicsAngle-resolved photoemission spectroscopyMaterials scienceBand gapPhysicsTransition (genetics)Phase (matter)Metal–insulator transitionSpectral lineMolecular physicsInsulator (electricity)Electronic band structureEnergy (signal processing)Chemistry2D Materials and ApplicationsHeusler alloys: electronic and magnetic propertiesTopological Materials and Phenomena