Quasi-one-dimensional topological band structure and van Hove singularities in monolayer TaIrTe4 from laser μ-ARPES

Rapport Preprint Quasi-one-dimensional topological band structure and van Hove singularities in monolayer TaIrTe4 from laser μ-ARPES eng 2026-08-21 2026-08-21 author Boban Honey 429379 Département de physique de la matière quantique (FIMAC) author Prongué Tanguy François Jean 945981 Département de physique de la matière quantique (FIMAC) author Choudhury Amarjyoti author Marchiani Dario 432333 Département de physique de la matière quantique (FIMAC) author Bareño Prieto Andres Felipe 430161 Département de physique de la matière quantique (FIMAC) author Eder Félix 417228 author Giannini Enrico 0000-0003-3536-4771 503364 Département de physique de la matière quantique (FIMAC) author von Rohr Fabian 973176 Département de physique de la matière quantique (FIMAC) Fabian Oliver Von Rohr author Morpurgo Alberto 666794 Département de physique de la matière quantique (FIMAC) author Gibertini Marco author Tamai Anna 0000-0001-5239-6826 795188 Département de physique de la matière quantique (FIMAC) author Baumberger Felix 0000-0001-7104-7541 790217 MaNEP DIP (MANSC) Félix Baumberger 2608.20978v1 Recent transport experiments reported a quantum spin Hall insulator phase in monolayer 1T-TaIrTe4 gated away from charge neutrality. This phase is not predicted by band structure calculations and has been attributed to an electronic instability induced by strong correlations at a putative van Hove singularity. Here, we investigate the electronic structure of exfoliated monolayer 1T-TaIrTe4 using micro-focus laser angle resolved photoemission. We find a strongly anisotropic band structure susceptible to density wave instabilities. Our data further reveal a saddle point singularity in the density of states. However, we find that the saddle point lies at a density for which transport experiments found no anomalies. Moreover, the quasiparticle line widths suggest weak electron correlations only. This points to a secondary role of van Hove singularities and electron correlations in the transport phase diagram of monolayer 1T-TaIrTe4. Dewey 500.2 33 Département de physique de la matière quantique 131 false 805 Groupe Baumberger 1383 Groupe von Rohr 678 Groupe Morpurgo de89c688-11ee-4095-a8c3-36801eeb893c Preprint Public Article_scientifique_from_arxiv.pdf 8031258 application/pdf CC BY-4.0 28b1e41bfef55dd907fa5a158c7cb1345c1e3efc5a84459e94da7cd057413427 openAccess Faculté des sciences / Section de physique / Département de physique de la matière quantique

Title	Published in	Access level	OA Policy	Year	Views	Downloads

Quasi-one-dimensional topological band structure and van Hove singularities in monolayer TaIrTe₄ from laser μ-ARPES				2026	1	0

Archive ouverte UNIGE

Boban, Honey