Simultaneous three-photon absorption induced ultraviolet upconversion in Pr3+:Y2SiO5 crystal by femtosecond laser irradiation

Abstract: Near-infrared to ultraviolet upconversion luminescence was observed in the Pr3+:Y2SiO5 crystal with 120fs, 800nm infrared laser irradiation. The observed emissions at around 270nm and 305nm could be assigned to 5d→4f transitions of Pr3+ ions. The relationship between the upconversion luminescence intensity and the pump power of the femtosecond laser reveals that the UV emission belongs to simultaneous three-photon absorption induced upconversion luminescence. [Copyright &y& Elsevier]