Investigating the structure-sensitive factors relevant to cryogenic laser operation of Yb3+ ions in oxide crystals

Optical absorption and luminescence spectra of Yb3+ ions in Gd3(Al0.5Ga0.5)5O12, (Lu0.3Gd0.7)2SiO5 and YAl3(BO3)4 hosts crystals were examined as a function of temperature between 80 and 300 K. The analysis of obtained data provided detailed information on the thermally induced change of intensities, wavelengths and bandwidths of Yb3+ transitions that governs the temperature dependence of absorption and emission cross section spectra. This information, combined with structural peculiarities of the systems studied made it possible to propose generalizations regarding the importance of the structural disorder in the Yb3+-doped laser crystals operating at cryogenic temperatures.