title: Blue upconversion luminescence generation in Ce3+:Gd2SiO5 crystals by infrared femtosecond laser irradiation.
abstract: Blue frequency-upconversion fluorescence emission has been observed in Ce(3+)-doped Gd(2)SiO(5) single crystals, pumped with 120-fs 800 nm IR laser pulses. The observed fluorescence emission peaks at about 440nm is due to 5d?4f transition of Ce3+ ions. The intensity dependence of the blue fluorescence emission on the IR excitation laser power obeys the cubic law, demonstrating three-photon absorption process. Analysis suggested that three-photon simultaneous absorption induced population inversion should be the predominant frequency upconversion mechanism.
authors.forename: Yongjun
authors.initials: Y
authors.lastname: Dong
authors.forename: Jun
authors.initials: J
authors.lastname: Xu
authors.forename: Guoqing
authors.initials: G
authors.lastname: Zhou
authors.forename: Guangjun
authors.initials: G
authors.lastname: Zhao
authors.forename: Mingyin
authors.initials: M
authors.lastname: Jie
authors.forename: Luyun
authors.initials: L
authors.lastname: Yang
authors.forename: Liangbi
authors.initials: L
authors.lastname: Su
authors.forename: Jianrong
authors.initials: J
authors.lastname: Qiu
authors.forename: Weiwei
authors.initials: W
authors.lastname: Feng
authors.forename: Lihuang
authors.initials: L
authors.lastname: Lin