Measurement of gain saturation in Nd:doped phosphate laser glasses

Saturation of gain was studied in Nd:doped phosphate glasses LHG-8 and LG-760 using the laser beam with wavelength of 1.053 μm and pulse width of 1 ns. Saturation fluence was calculated by use of Frantz-Nodvik equation from the input fluence, the output fluence and the small signal gain. The saturation fluence E s is related to output fluence E out , which is, E s = 3.04 + 0.149 E out J/cm 2 in case of LHG-8 and E s = 2.70 + 0.170 E out J/cm 2 in case of LG-760.