文摘
Monolayer MoS2 is a direct-gap two-dimensional semiconductor that exhibits strong electron鈥揾ole interactions, leading to the formation of stable excitons and trions. Here we report the existence of efficient exciton鈥揺xciton annihilation, a four-body interaction, in this material. Exciton鈥揺xciton 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鈥揺xciton annihilation was determined to be (4.3 卤 1.1) 脳 10鈥? cm2/s at room temperature.
Keywords:
MoS2; transient absorption spectroscopy; exciton dynamics; exciton鈭抏xciton annihilation