Abstract

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 WS2 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.

Microcavity exciton-polaritons in atomically thin semiconductors are a promising platform for valley manipulation. Here, the authors show valley-selective control of polariton energies in monolayer WS2 using the optical Stark effect, thereby extending coherent valley manipulation to a hybrid light-matter regime

Details

Title
Valley-selective optical Stark effect of exciton-polaritons in a monolayer semiconductor
Author
LaMountain Trevor 1 ; Nelson, Jovan 1 ; Lenferink, Erik J 2 ; Amsterdam, Samuel H 3 ; Murthy, Akshay A 4   VIAFID ORCID Logo  ; Zeng Hongfei 2 ; Marks, Tobin J 5   VIAFID ORCID Logo  ; Dravid, Vinayak P 6   VIAFID ORCID Logo  ; Hersam, Mark C 7   VIAFID ORCID Logo  ; Stern, Nathaniel P 8   VIAFID ORCID Logo 

1  Northwestern University, Applied Physics Program, Evanston, USA (GRID:grid.16753.36) (ISNI:0000 0001 2299 3507) 
2  Northwestern University, Department of Physics and Astronomy, Evanston, USA (GRID:grid.16753.36) (ISNI:0000 0001 2299 3507) 
3  Northwestern University, Department of Chemistry and the Materials Research Center, Evanston, USA (GRID:grid.16753.36) (ISNI:0000 0001 2299 3507) 
4  Northwestern University, Department of Materials Science and Engineering and the Materials Research Center, Evanston, USA (GRID:grid.16753.36) (ISNI:0000 0001 2299 3507); Northwestern University, International Institute of Nanotechnology, Evanston, USA (GRID:grid.16753.36) (ISNI:0000 0001 2299 3507) 
5  Northwestern University, Department of Chemistry and the Materials Research Center, Evanston, USA (GRID:grid.16753.36) (ISNI:0000 0001 2299 3507); Northwestern University, Department of Materials Science and Engineering and the Materials Research Center, Evanston, USA (GRID:grid.16753.36) (ISNI:0000 0001 2299 3507) 
6  Northwestern University, Department of Materials Science and Engineering and the Materials Research Center, Evanston, USA (GRID:grid.16753.36) (ISNI:0000 0001 2299 3507); Northwestern University, International Institute of Nanotechnology, Evanston, USA (GRID:grid.16753.36) (ISNI:0000 0001 2299 3507); Northwestern University, NUANCE Center, Evanston, USA (GRID:grid.16753.36) (ISNI:0000 0001 2299 3507) 
7  Northwestern University, Applied Physics Program, Evanston, USA (GRID:grid.16753.36) (ISNI:0000 0001 2299 3507); Northwestern University, Department of Chemistry and the Materials Research Center, Evanston, USA (GRID:grid.16753.36) (ISNI:0000 0001 2299 3507); Northwestern University, Department of Materials Science and Engineering and the Materials Research Center, Evanston, USA (GRID:grid.16753.36) (ISNI:0000 0001 2299 3507); Northwestern University, Department of Electrical and Computer Engineering, Evanston, USA (GRID:grid.16753.36) (ISNI:0000 0001 2299 3507) 
8  Northwestern University, Applied Physics Program, Evanston, USA (GRID:grid.16753.36) (ISNI:0000 0001 2299 3507); Northwestern University, Department of Physics and Astronomy, Evanston, USA (GRID:grid.16753.36) (ISNI:0000 0001 2299 3507) 
Publication year
2021
Publication date
2021
Publisher
Nature Publishing Group
e-ISSN
20411723
Source type
Scholarly Journal
Language of publication
English
DOI
https://doi.org/10.1038/s41467-021-24764-8
ProQuest document ID
2555230798
Copyright
© The Author(s) 2021. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.