Orange-red upconversion luminescence of Sm3+-doped ZnO-B2O3-SiO2 glass by infrared femtosecond laser irradiation

Near-infrared-to-visible upconversion luminescence was observed in Sm3+-doped ZnO-B2O3-SiO2 glass under femtosecond laser irradiation. The luminescence spectra show that the upconversion luminescence originates from 4G(5/2) to H-6(j/2) (j = 5, 7, 9) transition of Sm3+. The dependence of the fluorescence intensity of Sm3+ on the pump power indicates that a two-photon absorption process is dominant in the conversion of infrared radiation to the visible luminescence. The analysis of the upconversion mechanism reveals that the simultaneous absorption of two infrared photons produces the population of upper excited states, which leads to the characteristic orange-red emission of Sm3+. A three-dimensional display is demonstrated based on the multiphoton absorption upconversion luminescence.