High magnetic field spin-valley-split Shubnikov-de Haas oscillations in a WSe2 monolayer

Banan Kerdi (1) , Mathieu Pierre (1) , Robin Cours (2) , Bénédicte Warot-Fonrose (3) , Michel Goiran (1) , Walter Escoffier (1)

1 LNCMI-T - Laboratoire national des champs magnétiques intenses - Toulouse
2 CEMES - Centre d'élaboration de matériaux et d'études structurales
3 CEMES-I3EM - Interférométrie, In situ et Instrumentation pour la Microscopie Electronique

We study Shubnikov-de Haas oscillations in a p-type WSe2 monolayer under very high magnetic field. The oscillation pattern is complex due to a large spin and valley splitting, in the non-fully-resolved Landau level regime. Our experimental data can be reproduced with a model in which the main parameter is the ratio between the Zeeman energy and the cyclotron energy. The model takes into account the Landau levels from both valleys with the same Gaussian broadening, which allows to predict the relative amplitude of the resistance oscillation originating from each valley. The Zeeman energy is found to be several times larger than the cyclotron energy. It translates into a large and increasing effective Landé factor as the hole density decreases, in the continuity of the values reported in the literature at lower carrier density.

Mots clés: Transition metal dichalcogenides (TMDCs); WSe2 monolayers; magneto-transport; high magnetic field physics; Zeeman effect; Landé factor; Landau levels; Shubnikov–de Haas oscillations

Domaines: Matière Condensée [cond-mat]; Systèmes mésoscopiques et effet Hall quantique [cond-mat.mes-hall]; Science des matériaux [cond-mat.mtrl-sci]; Electrons fortement corrélés [cond-mat.str-el]

Banan Kerdi, Mathieu Pierre, Robin Cours, Bénédicte Warot-Fonrose, Michel Goiran, et al.. High magnetic field spin-valley-split Shubnikov-de Haas oscillations in a WSe2 monolayer. Physical Review B, 2020, Physical Review B, 102, pp.155106. ⟨10.1103/PhysRevB.102.155106⟩. ⟨hal-02955379⟩