Excitons, electron-hole pairs in semiconductors, can be utilized as information carriers with a spin or valley degree of freedom. However, manipulation of excitons' motion is challenging because of their charge-neutral characteristic and short recombination lifetimes. Here we demonstrate electric-field-driven drift and funneling of charged excitons (i.e., trions) toward the center of a MoSe2monolayer. Using a simple bottom-gate device, we control the electric fields in the vicinity of the suspended monolayer, which increases the trion density and pulls down the layer. We observe that locally excited trions are subjected to electric force and, consequently, drift toward the center of the stretched layer. The exerting electric force on the trion is estimated to be 102-104times stronger than the strain-induced force in the stretched monolayer, leading to the successful observation of trion drift under continuous-wave excitation. Our findings provide a new route for manipulating trions and achieving new types of optoelectronic devices.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation of Korea (NRF-2019R1A2C2003313) and the National R&D Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (2020M3H3A1105796, 2021M3F3A2A03017083). W.H.C. and D.L. acknowledge financial support from an NRF of Korea grant funded by the Korean government (MSIT) (NRF-2021R1F1A1049355).
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- suspended layer
- transition-metal dichalcogenide
- trion drift
ASJC Scopus subject areas
- General Chemistry
- General Materials Science
- Condensed Matter Physics
- Mechanical Engineering