Upconversion luminescense properties of holmium co-doped ZrF4-BiF3 ceramics

摘要

The conversion of infrared radiation of a Tm3+:YAP laser at a wavelength of 1.93 mu m into visible light in [(ZrF4)(0.4)-(BiF3)(0.6)](100-x)-(HoF3)(x) (x = 1.5 or 5 wt%) ceramic samples was investigated. The emission bands at wavelengths of 650 nm, 900 nm and 1100 nm corresponding to transitions from F-5(5), I-5(5) and I-5(6) levels to the ground state I-5(8) were observed in upconversion luminescence spectra. From the experimental data, an estimate of the crossrelaxation coefficient from S-5(2) was obtained. It was K-cr approximate to 1 x 10(-16) cm(3) s(-1). The threshold power density of Tm3+:YAP laser, at which a luminescence was observed on the ceramic samples, was about 0.85 W cm(-2).