Magnetic-field-induced splitting and polarization of monolayer-based valley exciton polaritons
Abstract
Atomically thin crystals of transition metal dichalcogenides are ideally suited to study the interplay of light-matter coupling, polarization, and magnetic field effects. In this work, we investigate the formation of exciton-polaritons in a MoSe2 monolayer, which is integrated in a fully-grown, monolithic microcavity. Due to the narrow linewidth of the polaritonic resonances, we are able to directly investigate the emerging valley Zeeman splitting of the hybrid light-matter resonances in the presence of a magnetic field. At a detuning of -54.5 meV (13.5 % matter constituent of the lowerpolariton branch), we find a Zeeman splitting of the lower polariton branch of 0.36 meV, which can be directly associated with an excitonic g factor of 3.94±0.13. Remarkably, we find that a magnetic field of 6 T is suffcient to induce a notable valley polarization of 15 % in our polariton system, which approaches 30% at 9 T. This circular polarization degree of the polariton (ground) state exceeds the polarization of the exciton reservoir for equal magnetic field magnitudes by approximately 50%, which is a clear hint of valley-dependent bosonic stimulation in our strongly coupled system in the sub-threshold, fluctuation dominated regime.
Citation
Lundt , N , Klaas , M , Sedov , E , Waldherr , M , Knopf , H , Blei , M , Tongay , S , Klembt , S , Taniguchi , T , Watanabe , K , Schulz , U , Kavokin , A , Höfling , S , Eilenberger , F & Schneider , C 2019 , ' Magnetic-field-induced splitting and polarization of monolayer-based valley exciton polaritons ' , Physical Review. B, Condensed matter and materials physics , vol. 100 , 121303(R) . https://doi.org/10.1103/PhysRevB.100.121303
Publication
Physical Review. B, Condensed matter and materials physics
Status
Peer reviewed
ISSN
1098-0121Type
Journal article
Rights
Copyright © 2019 American Physical Society. This work has been made available online in accordance with publisher policies or with permission. Permission for further reuse of this content should be sought from the publisher or the rights holder. This is the author created accepted manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at https://doi.org/10.1103/PhysRevB.100.121303
Description
he Würzburg group acknowledges support by the state of Bavaria. C.S. acknowledges support by the European Research council (ERC) under the European Union's Horizon 2020 Research and Innovation Programme (UnLiMIt-2D), Grant Agreement No. 679288. This work has been supported by the Fraunhofer-Gesellschaft zur Föderung der angewandten Forschung e.V. F.E. and H.K. gratefully acknowledge the financial support by the German Federal Ministry of Education and Research under Grant No. 13XP5053A. E.S. acknowledges support from the Grant of the President of the Russian Federation for state support of Young Russian Scientists, Grant No. MK-2839.2019.2 and RFBR Grant No. 17-52-10006. The work of A.K. is supported by Westlake University (Project No. 041020100118). S.T. acknowledges support from NSF, Grant No. DMR-1838443.Collections
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