Speaker: Manuel Fernandez Lopez
Affiliation: Departamento de Física Teórica de la Materia Condensada, Condensed Matter Physics Center (IFIMAC) and Instituto Nicolás Cabrera, Universidad Autónoma de Madrid
Abstract
Motivated by the anomalous metallic properties observed in many strongly correlated materials we explore the Mott transition in honeycomb compounds with significant spin-orbit coupling. Based on a slave-rotor approach to the Kane-Mele-Hubbard model we identify a novel semimetallic phase arising at finite temperatures between a topological insulator and a topological Mott insulator. This semimetal is characterized by having no charge gap, no quasiparticles and gapped spin excitations with non-trivial topological properties. While charge conduction is incoherent involving mean-free paths violating the Mott-Ioffe-Regel limit, spin excitations can be transported ballistically along the edges giving rise to a quantized spin conductance. Such bad topological semimetal can be searched for close to the Mott transition in certain twisted bilayers of transition metal dicalchogenides.
[1] M. F. López and J. Merino, Phys. Rev. B, 105, 115138 (2022).
About Physics Seminars
The weekly Physics Seminar series focuses on a broad range of physics research within SMP, along with frequent presentations from visiting researchers. Seminars are usually scheduled for 1.00pm on Tuesdays.
The talks are typically more specialised than a colloquium but are often attended by staff and PhD students across a broad range of areas. Speakers are thus encouraged to include introductory material in the talks.
All SMP researchers and HDR students are encouraged to speak. Please email Lewis Williamson to register your interest.
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