Autoionization and Dressing of Excited Excitons by Free Carriers in Monolayer WSe2
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Contributors
Abstract
We experimentally demonstrate dressing of the excited exciton states by a continuously tunable Fermi sea of free charge carriers in a monolayer semiconductor. It represents an unusual scenario of two-particle excitations of charged excitons previously inaccessible in conventional material systems. We identify excited state trions, accurately determine their binding energies in the zero-density limit for both electron- and hole-doped regimes, and observe emerging many-body phenomena at elevated doping. Combining experiment and theory we gain access to the intra-exciton coupling facilitated by the interaction with free charge carriers. We provide evidence for a process of autoionization for quasiparticles, a unique scattering pathway available for excited states in atomic systems. Finally, we demonstrate a complete transfer of the optical transition strength from the excited excitons to dressed Fermi-polaron states as well as the associated light emission from their nonequilibrium populations.
Details
Original language | English |
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Article number | 267401 |
Journal | Physical review letters |
Volume | 125 |
Issue number | 26 |
Publication status | Published - 21 Dec 2020 |
Peer-reviewed | Yes |
Externally published | Yes |
External IDs
PubMed | 33449708 |
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