Up-conversion luminescence in mixed crystals BaY1.8Lu0.2F8 doped with Er3+ ions excited at 1532 nm.

Increasing the efficiency of upconversion luminophores is an important problem in materials science. Here we report on approach of use of disordered crystals namely solid solutions BaY1.8Lu0.2F8 doped with Er3+ ions to improve spectral characteristics and efficiency of upconversion from near IR spectral region. It is shown that investigated compound provide up to 9.4% of external energy yield of the up-conversion luminescence at an excitation power density of 6 W/cm2 at 1532 nm for the 10 at.% of Er3+ doping. Also the investigated crystals of BaY1.8Lu0.2F8:Er3+ allow the control of the CCT parameter in the range of 2384–5149 K by changing the concentration and power density of the excitation. Advantages revealed in this work for crystalline compounds BaY1.8Lu0.2F8:Er3+ such as wide absorption bands in the infrared spectral range, a high external energy yield, and a controllable distribution of intensity of luminescence bands makes them prospective to improve the efficiency of double-sided solar cells