Valley-selective optical Stark effect of exciton-polaritons in a monolayer semiconductor.

Autor: LaMountain T; Applied Physics Program, Northwestern University, Evanston, IL, 60208, USA., Nelson J; Applied Physics Program, Northwestern University, Evanston, IL, 60208, USA., Lenferink EJ; Department of Physics and Astronomy, Northwestern University, Evanston, IL, 60208, USA., Amsterdam SH; Department of Chemistry and the Materials Research Center, Northwestern University, Evanston, IL, 60208, USA., Murthy AA; Department of Materials Science and Engineering and the Materials Research Center, Northwestern University, Evanston, IL, 60208, USA.; International Institute of Nanotechnology, Northwestern University, Evanston, IL, 60208, USA., Zeng H; Department of Physics and Astronomy, Northwestern University, Evanston, IL, 60208, USA., Marks TJ; Department of Chemistry and the Materials Research Center, Northwestern University, Evanston, IL, 60208, USA.; Department of Materials Science and Engineering and the Materials Research Center, Northwestern University, Evanston, IL, 60208, USA., Dravid VP; Department of Materials Science and Engineering and the Materials Research Center, Northwestern University, Evanston, IL, 60208, USA.; International Institute of Nanotechnology, Northwestern University, Evanston, IL, 60208, USA.; NUANCE Center, Northwestern University, Evanston, IL, 60208, USA., Hersam MC; Applied Physics Program, Northwestern University, Evanston, IL, 60208, USA.; Department of Chemistry and the Materials Research Center, Northwestern University, Evanston, IL, 60208, USA.; Department of Materials Science and Engineering and the Materials Research Center, Northwestern University, Evanston, IL, 60208, USA.; Department of Electrical and Computer Engineering, Northwestern University, Evanston, IL, 60208, USA., Stern NP; Applied Physics Program, Northwestern University, Evanston, IL, 60208, USA. n-stern@northwestern.edu.; Department of Physics and Astronomy, Northwestern University, Evanston, IL, 60208, USA. n-stern@northwestern.edu.
Jazyk: angličtina
Zdroj: Nature communications [Nat Commun] 2021 Jul 26; Vol. 12 (1), pp. 4530. Date of Electronic Publication: 2021 Jul 26.
DOI: 10.1038/s41467-021-24764-8
Abstrakt: Selective breaking of degenerate energy levels is a well-known tool for coherent manipulation of spin states. Though most simply achieved with magnetic fields, polarization-sensitive optical methods provide high-speed alternatives. Exploiting the optical selection rules of transition metal dichalcogenide monolayers, the optical Stark effect allows for ultrafast manipulation of valley-coherent excitons. Compared to excitons in these materials, microcavity exciton-polaritons offer a promising alternative for valley manipulation, with longer lifetimes, enhanced valley coherence, and operation across wider temperature ranges. Here, we show valley-selective control of polariton energies in WS 2 using the optical Stark effect, extending coherent valley manipulation to the hybrid light-matter regime. Ultrafast pump-probe measurements reveal polariton spectra with strong polarization contrast originating from valley-selective energy shifts. This demonstration of valley degeneracy breaking at picosecond timescales establishes a method for coherent control of valley phenomena in exciton-polaritons.
(© 2021. The Author(s).)
Databáze: MEDLINE
Externí odkaz: