Scientists investigated how excitons (quantum particles produced in semiconductors) move in thin layers of WSe₂ and WS₂ materials at very low temperatures.[1][2] They discovered a surprising phenomenon: when the system was located close to the electronic Mott insulator, the diffusion of excitons increased a thousandfold compared to the state without electric charge.[1][3] They explain this unexpected increase in mobility by mobile holes in the material, which experience a weakened potential due to the arrangement of the charge and recombine with electrons in a non-standard way.[1][3] Research demonstrates that exciton diffusion can serve as a tool to probe complex electronic states in semiconductor structures.[1] These findings open up possibilities for the development of new electronic and optical devices with improved properties.[7] The study was published in the journal Science in January 2026 and was the result of a collaboration between research teams from the University of Maryland, the University of Geneva and other institutions.[2]