Exploring Structure-Sensitive Factors Relevant to Cryogenic Laser Operation in Oxide Crystals Doped with Er(3+) Ions

Crystals of Gd(3)Al(2.5)Ga(2.5)O(12):Er(3+), (Lu(0.3)Gd(0.7))(2)SiO(5):Er(3+) and LiNbO(3):Er(3+) compounds differing in origin and the nature of their inherent structural disorder were crystalized. Optical absorption and luminescence spectra for transitions between the (4)I(15/2) and the (4)I(13/2) multiplets of Er(3+) ions for the crystal samples were recorded versus temperatures in the region of 80–300 K. Gathered data were analyzed thoroughly providing the in-depth knowledge of the effects of temperature on intensities, wavelengths and bandwidths of Er(3+) transitions. The information acquired together with the knowledge of significant structural dissimilarities of the host crystals chosen made it possible to propose an interpretation of the impact of a structural disorder in Er(3+)-doped crystals on their spectroscopic properties, and to determine their lasing ability at cryogenic temperatures upon resonant (in-band) optical pumping.