ANALYSES FOR LASING THRESHOLD AT 2 AND 1.5μm WAVELENGTHS IN Tm:YVO₄ CRYSTAL

From transition-rate-equations and transmission-equations the formulas of threshold power are deduced for an end-pumped laser, in which the probability of cross-relaxation cannot be ignored and the nonradiative transition-probability of the excited state is the same order as the radiative transition-probability of upper level of the lasing transition. The lasing performance of Tm:YVO₄ at \lambda=1.9 and 1.5μm is discussed by dint of these equations of threshold power.