KIT | KIT-Bibliothek | Impressum | Datenschutz

Band hybridization at the semimetal-semiconductor transition of Ta 2NiSe 5 enabled by mirror-symmetry breaking

Watson, Matthew D.; Marković, Igor; Morales, Edgar Abarca; Le Fèvre, Patrick; Merz, Michael; Haghighirad, Amir A.; King, Philip D. C.

Abstract:

We present a combined study from angle-resolved photoemission and density-functional-theory calculations of the temperature-dependent electronic structure in the excitonic insulator candidate Ta$_{2}$NiSe$_{5}$. Our experimental measurements unambiguously establish the normal state as a semimetal with a significant band overlap of >100 meV. Our temperature-dependent measurements indicate how these low-energy states hybridize when cooling through the well-known 327 K phase transition in this system. From our calculations and polarization-dependent photoemission measurements, we demonstrate the importance of a loss of mirror symmetry in enabling the band hybridization, driven by a shearlike structural distortion which reduces the crystal symmetry from orthorhombic to monoclinic. ... mehr

Abstract (englisch):

We present a combined study from angle-resolved photoemission and density-functional-theory calculations of the temperature-dependent electronic structure in the excitonic insulator candidate Ta2NiSe5. Our experimental measurements unambiguously establish the normal state as a semimetal with a significant band overlap of >100 meV. Our temperature-dependent measurements indicate how these low-energy states hybridize when cooling through the well-known 327 K phase transition in this system. From our calculations and polarizationdependent photoemission measurements, we demonstrate the importance of a loss of mirror symmetry in enabling the band hybridization, driven by a shearlike structural distortion which reduces the crystal symmetry from orthorhombic to monoclinic. ... mehr


Verlagsausgabe §
DOI: 10.5445/IR/1000117678
Veröffentlicht am 28.11.2021
Originalveröffentlichung
DOI: 10.1103/PhysRevResearch.2.013236
Dimensions
Zitationen: 63
Cover der Publikation
Zugehörige Institution(en) am KIT Institut für QuantenMaterialien und Technologien (IQMT)
Publikationstyp Zeitschriftenaufsatz
Publikationsdatum 02.03.2020
Sprache Englisch
Identifikator ISSN: 2643-1564
KITopen-ID: 1000117678
HGF-Programm 43.21.01 (POF III, LK 01) Quantum Correlations in Condensed Matter
Erschienen in Physical review research
Verlag American Physical Society (APS)
Band 2
Heft 1
Seiten Article no: 013236
Vorab online veröffentlicht am 29.02.2020
Schlagwörter Band hybridization at the semimetal-semiconductor; 2019-022-025949; 2020-024-029049 WERA
Nachgewiesen in Dimensions
KIT – Die Forschungsuniversität in der Helmholtz-Gemeinschaft
KITopen Landing Page