Observation of rapid exciton-exciton annihilation in monolayer molybdenum disulfide

Nano Lett. 2014 Oct 8;14(10):5625-9. doi: 10.1021/nl5021975. Epub 2014 Sep 9.


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.

Keywords: MoS2; exciton dynamics; exciton−exciton annihilation; transient absorption spectroscopy.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.