Observation of rapid exciton-exciton annihilation in monolayer molybdenum disulfide.
نویسندگان
چکیده
Monolayer MoS2 is a direct-gap two-dimensional semiconductor that exhibits strong electron-hole interactions, leading to the formation of stable excitons and trions. Here we report the existence of efficient exciton-exciton annihilation, a four-body interaction, in this material. Exciton-exciton annihilation was identified experimentally in ultrafast transient absorption measurements through the emergence of a decay channel varying quadratically with exciton density. The rate of exciton-exciton annihilation was determined to be (4.3 ± 1.1) × 10(-2) cm(2)/s at room temperature.
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ورودعنوان ژورنال:
- Nano letters
دوره 14 10 شماره
صفحات -
تاریخ انتشار 2014