Valley-Polarized Exciton Dynamics in Exfoliated Monolayer WSe
arXiv:1703.05005 · doi:10.1021/acs.jpcc.7b01468
Abstract
Semiconducting transition metal dichalcogenide monolayers have emerged as promising candidates for future valleytronics-based quantum information technologies. Two distinct momentum-states of tightly-bound electron-hole pairs in these materials can be deterministically initialized via irradiation with circularly polarized light. Here, we investigate the ultrafast dynamics of such a valley polarization in monolayer tungsten diselenide by means of time-resolved Kerr reflectometry. The observed Kerr signal in our sample stems exclusively from charge-neutral excitons. Our findings support the picture of a fast decay of the valley polarization of bright excitons due to radiative recombination, intra-conduction-band spin-flip transitions, intervalley-scattering processes, and the formation of long-lived valley-polarized dark states.
arXiv commentThis document is the unedited Author's version of a Submitted Work that was subsequently accepted for publication in The Journal of Physical Chemistry C, copyright American Chemical Society after peer review. To access the final edited and published work see http://pubs.acs.org/articlesonrequest/AOR-hCJpKkDiPY2E8AZzPe3t
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Cited by in corpus (6)
- Nanophotonics with 2D Transition Metal Dichalcogenides
- Momentum-Resolved Exciton Coupling and Valley Polarization Dynamics in Monolayer WS
- Valley Dynamics of Excitons in Monolayer Dichalcogenides
- Long-lived spin polarization in n-doped MoSe monolayers
- Spin-valley dynamics in alloy-based transition metal dichalcogenide heterobilayers
- Valley-Selective Response of Nanoantennas Coupled to 2D Transition Metal Dichalcogenides