Rise Kinetics of Up-Conversion Luminescence of the LiY0.8Yb0.2F4:Tm3+ (0.2 at %) Crystal with Pulsed Excitation

Abstract

The regression analysis of the rise kinetics of up-conversion luminescence of the LiY0.8Yb0.2F4:Tm3+ (0.2 at %) crystal is performed. The kinetics curve is obtained with rectangular pulsed excitation by radiation from a laser diode (IR LD) with a wavelength of λp = 933 nm. The most important—in these experimental conditions—mechanisms of the energy transfer from Yb3+ ions to Tm3+ ions are established, which are responsible for the transitions between the ground 3H6 and excited 3F4, 3H4, 1G4, 1D2, and 1I6 terms of the Tm3+ ions. The durations of the relevant energy transfer processes are determined. It is shown that the energy transfer between rare earth ions in the LiY0.8Yb0.2F4:Tm3+ (0.2 at %) crystal occurs through the dipole–dipole interactions.