NEW PHOTOCALORIMETRIC COMPENSATION TECHNIQUE FOR DETERMINING ABSOLUTE FLUORESCENCE QUANTUM EFFICIENCIES OF OPTICALLY-ACTIVE IONS IN LASER MATERIALS

A new photocalorimetric compensation technique is described for determining the absolute fluorescence quantum efficiencies and optical heating efficiencies of optically active ions in laser materials. The method requires a continuous laser source but does not require knowledge of either the thermal properties of the sample or the absolute temperature, and absolute calibration of the laser power is not necessary. The technique has been successfully tested by investigation of a ruby sample, where the absolute fluorescence quantum efficiencies of the green and the blue bands were determined to be the same within experimental error, viz. 0.710 +/- 0.005.