Abstract
Exciton transport is a fundamental process that underlies the functionality of semiconductor optoelectronicdevices. However, when excitons interact with one another, their transport pattern becomes unpredictable, posinga great challenge to harness their full potential in various applications. In our study, focusing on the excitondensity change in a tungsten-disulfide monolayer, we observed that strong interactions between excitons canactually stop their movement. This finding contradicts the typical understanding of consistent exciton movementand reveals that a higher density might decrease the exciton-exciton annihilation rate due to reduced mobility.Our findings offer a valuable technique to examine exciton transport and deepen our grasp of their behavior inmany-body interactions, which could pave the way for better-performing excitonic devices.