%0 Conference Proceedings
%T Temperature dependance of Intrinsic Spin Orbit Coupling Gap in Graphene probed by Terahertz photoconductivity
%+ Institut d’Electronique et des Systèmes (IES)
%+ Modélisation et Spectroscopie THz (MOST)
%+ Laboratoire Charles Coulomb (L2C)
%+ Universidad de Salamanca [España] = University of Salamanca [Spain]
%+ Institute of High Pressure Physics [Warsaw] (IHPP)
%+ Universität Regensburg (UR)
%+ Wroclaw University of Science and Technology
%+ Chalmers University of Technology [Göteborg]
%A Maussang, Kenneth
%A Dinar, Khalid
%A Bray, Cédric
%A Consejo, Christophe
%A Delgado-Notario, J.
%A Krishtopenko, Sergey
%A Yahniuk, Ivan
%A Gerbert, S.
%A Ruffenach, Sandra
%A Moench, E.
%A Indykiewicz, Kornelia
%A Benhamou-Bui, Benjamin
%A Jouault, Benoit
%A Torres, Jérémie
%A Meziani, Y, M
%A Knap, Wojciech
%A Yurgens, A.
%A Ganichev, S.
%A Teppe, Frédéric
%< avec comité de lecture
%B 2023 48th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz)
%C Montréal, Canada
%I IEEE
%3 2023 48th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz)
%8 2023-09-17
%D 2023
%R 10.1109/irmmw-thz57677.2023.10299006
%Z Physics [physics]/Condensed Matter [cond-mat]Conference papers
%X Graphene is a quantum spin Hall insulator, with a nontrivial topological gap induced by the spin-orbit coupling. Such splitting is weak (~45µeV) in the absence of external magnetic field. However, due to rather long spin-relaxation time, graphene is an attractive candidate for applications in quantum technologies. When it is encapsulated in hexagonal boron nitride, the coupling between graphene and the substrate compensates intrinsic spin-orbit coupling and decreases the nontrivial topological gap, which may lead to phase transition into a trivial band insulator state. In this work, we have measured experimentally the zero-field splittings in monolayer and bilayer graphene by the means of subterahertz photoconductivity-based electron spin resonance technique. The dependance in temperature of such splittings have been also studied in the 2-12K range. We observed a decrease of the spin splittings with increasing temperature. Such behavior might be understood from several physical mechanisms that could induce a temperature dependence of the spin-orbit coupling. These includes the difference in the expansion coefficients between the graphene and the boron nitride substrate or the metal contacts, the electronphonon interactions, and the presence of a magnetic order at low temperature.
%G English
%2 https://hal.science/hal-04304454v1/document
%2 https://hal.science/hal-04304454v1/file/IRMMW-THz2023_ABSTRACT-ESR-FT.pdf
%L hal-04304454
%U https://hal.science/hal-04304454
%~ CNRS
%~ IES
%~ L2C
%~ UNIV-MONTPELLIER
%~ UM-2015-2021
%~ UM-EPE