Ultrafast carrier dynamics in single-crystal In2Se3 thin layers

摘要

Carrier dynamics in single-crystal In2Se3 thin layers with various thicknesses was studied by femtosecond optical pump-probe reflectivity and ultrafast photocurrent measurements. The results suggest that, in thinner (thicker) layers, the carrier recombination dynamics is dominated by three-carrier (bimolecular) Auger process. The Auger time constant was found to decrease with deceasing layer thickness. Surface states were suggested to be the origin of the transition between different Auger processes as the layer thickness varies.