Manipulation of room-temperature Valley-Coherent Exciton-Polaritons in atomically thin crystals by real and artificial magnetic fields
| Autor: | Takashi Taniguchi, Falk Eilenberger, Kenji Watanabe, Alexey Kavokin, Christian Schneider, Christoph Rupprecht, Evgeny Sedov, Martin Klaas, Heiko Knopf, Sefaattin Tongay, Nils Lundt, Ulrike Schulz, Sven Höfling, Mark Blei |
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| Přispěvatelé: | University of St Andrews. Condensed Matter Physics, University of St Andrews. School of Physics and Astronomy, Publica |
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
excitons
NDAS FOS: Physical sciences Library science 02 engineering and technology magnetic fields 01 natural sciences transition metals Political science Mesoscale and Nanoscale Physics (cond-mat.mes-hall) 0103 physical sciences crystals General Materials Science 010306 general physics QC Condensed Matter - Materials Science Condensed Matter - Mesoscale and Nanoscale Physics Mechanical Engineering European research Materials Science (cond-mat.mtrl-sci) General Chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics monolayers QC Physics Mechanics of Materials Christian ministry Russian federation 0210 nano-technology Partial support |
| Zdroj: | 2D Materials |
| ISSN: | 2053-1583 |
| Popis: | Strong spin-orbit coupling and inversion symmetry breaking in transition metal dichalcogenide monolayers yield the intriguing effects of valley-dependent optical selection rules. As such, it is possible to substantially polarize valley excitons with chiral light and furthermore create coherent superpositions of K and K- polarized states. Yet, at ambient conditions dephasing usually becomes too dominant, and valley coherence typically is not observable. Here, we demonstrate that valley coherence is, however, clearly observable for a single monolayer of WSe2, if it is strongly coupled to the optical mode of a high quality factor microcavity. The azimuthal vector, representing the phase of the valley coherent superposition, can be directly manipulated by applying magnetic fields, and furthermore, it sensibly reacts to the polarization anisotropy of the cavity which represents an artificial magnetic field. Our results are in qualitative and quantitative agreement with our model based on pseudospin rate equations, accounting for both effects of real and pseudo-magnetic fields. 12 Pages, 5 Figures |
| Databáze: | OpenAIRE |
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