Exciton-Exciton Interaction beyond the Hydrogenic Picture in a MoSe2 Monolayer in the Strong Light-Matter Coupling Regime

作     者：Petr Stepanov Amit Vashisht Martin Klaas Nils Lundt Sefaattin Tongay Mark Blei Sven Höfling Thomas Volz Anna Minguzzi Julien Renard Christian Schneider Maxime Richard 

作者机构：Univ. Grenoble Alpes CNRS Grenoble INP Institut Néel 38000 Grenoble France Univ. Grenoble Alpes CNRS LPMMC 38000 Grenoble France Technische Physik and Wilhelm Conrad Röntgen Research Center for Complex Material Systems Physikalisches Institut Universität Würzburg Am Hubland D-97074 Würzburg Germany Arizona State University Tempe Arizona 85287 USA Department of Physics and Astronomy Macquarie University NSW 2109 Australia ARC Centre of Excellence for Engineered Quantum Systems Macquarie University NSW 2109 Australia Institute of Physics University of Oldenburg 26129 Oldenburg Germany 

出 版 物：《Physical Review Letters》 (物理评论快报)

年 卷 期：2021年第126卷第16期

页      面：167401-167401页

核心收录：

学科分类：07[理学] 0702[理学-物理学] 

基　　金：Marie Skłodowska-Curie Army Research Office, ARO Horizon 2020 European Research Commission, (697228) National Science Foundation, NSF, (1838443, 1838443) Agence Nationale de la Recherche, ANR, (ANR-15-IDEX-02, ANR-16-CE30-0021) Horizon 2020 Framework Programme, H2020, (754303) Australian Research Council, ARC, (CE170100009) 

主　　题：Exciton polariton Excitons Third order nonlinear optical processes Transition metal dichalcogenides 

摘      要：In transition metal dichalcogenides’ layers of atomic-scale thickness, the electron-hole Coulomb interaction potential is strongly influenced by the sharp discontinuity of the dielectric function across the layer plane. This feature results in peculiar nonhydrogenic excitonic states in which exciton-mediated optical nonlinearities are predicted to be enhanced compared to their hydrogenic counterparts. To demonstrate this enhancement, we perform optical transmission spectroscopy of a MoSe2 monolayer placed in the strong coupling regime with the mode of an optical microcavity and analyze the results quantitatively with a nonlinear input-output theory. We find an enhancement of both the exciton-exciton interaction and of the excitonic fermionic saturation with respect to realistic values expected in the hydrogenic picture. Such results demonstrate that unconventional excitons in MoSe2 are highly favorable for the implementation of large exciton-mediated optical nonlinearities, potentially working up to room temperature.