Absolute fluorescence quantum efficiency of GSGG : Cr at ambient temperature

The absolute fluorescence quantum efficiencies of three GSGG : Cr³⁺ samples have been determined at specific excitation wavelengths for the ⁴T₁and ⁴T₂ absorption bands using a novel photocalorimetric compensation technique [1]. For laser excitation in the ⁴T₁ and ⁴T₁ bands, the technique yields the same fluorescence quantum efficiency within experimental error for all three samples, viz. 0.840 ± 0.015. The effect of flourescence reabsorption on the measurements is discussed.