Effects of 946-nm thermal shift and broadening on Nd³⁺:YAG laser performance

Spectroscopic properties of flashlamp pumped Nd³⁺:YAG laser are studied as a function of temperature in a range from-30 ℃ to 60 ℃. The spectral width and shift of quasi three-level 946.0-nm inter-Stark emission within the respective intermanifold transitions of ⁴F_3/2→⁴I_9/2 are investigated. The 946.0-nm line shifts toward the shorter wavelength and broadens. In addition, the threshold power and slope efficiency of the 946.0-nm laser line are quantified with temperature. The lower the temperature, the lower the threshold power is and the higher the slope efficiency of the 946.0-nm laser line is, thus the higher the laser output is. This phenomenon is attributed to the ion-phonon interaction and the thermal population in the ground state.