Analysis of intrinsic optical bistability in Tm: YSGG laser crystal pumped under avalanche excitation at around 1um

摘要

Intrinsic optical bistability (IOB) in Tm: YSGG (yttrium-scandium-gallium garnet) laser crystal pumped at lum avalanche wavelength is predicted theoretically and studied numerically. The nonlinear rate equations of Tm: YSGG are given based on the nonlinear energy transfer processes. From the rate equations, the analytical formula of avalanche threshold condition is deduced in the steady-state approximation. Both the intrinsic bistability effect of population concentrations at Tm~(3+) levels versus pumping power and the influence of system parameters on IOB avalanche threshold are studied numerically. The results show that the avalanche threshold power of IOB can be changed by adjusting experimentally adjustable parameters such as the Tm~(3+) -dope concentration.