Research Studies on Neodymium Pentaphosphate Miniature Lasers.

摘要

The thermal conductivity and specific heat of NdP5O14 have been measured using a dynamic electrical heating technique. The values of the thermal conductivity tensor elements (in W/cm-K) are Lambda sub a = .021, Lambda sub b = .00966, and Lambda sub c = .014. The specific heat is 0.141 cal/g-K, in excellent agreement with the value of 0.139 cal/g-K that was measured by differential scanning calorimetry. We have calculated the time-dependent heating effects of typical flash-lamp-excited round and rectangular laser rods. With repetition rates limited to approx. 10 ppm, simple conductive cooling by an ambient-temperature heat-sink should be adequate. Computer simulation of the flash-lamp-excited NPP laser has been carried out by numerical solution of the laser rate equations. With 1 J electrical input, typical calculated output energies are 24 mJ for normal-mode operation and 10 mJ for passively Q-switched operation. Optimum Q-switch absorption and output mirror transmission have also been calculated. Experimental studies of such lasers have been made with varying laser rod size and laser resonator parameters.