NEODYMIUM--DOPED GLASS--CERAMIC LASER

Abstract

The lasing properties of glass-ceramic doped with $Nd^{3+}$ have been studied. The host consists of two phases, an anisotropic crystalline and an isotropic glassy one. The percentage of crystallinity can be controlled by heat treatment. The glass-ceramic host is characterized by very low thermal expansion. The size of the crystals vary from 100 to 300 {\AA} in diameter and the host material exhibits very low light scattering. The lasing threshold was found to be about two to three times larger than the threshold in $Nd^{3+}$-doped glass lasers, i.e., 90 joules for the glass-ceramic as compared to 40 joules for the glass laser rods. Furthermore, the lasing efficiency of the glass-ceramic laser is lower than the corresponding lasing efficiency of the glass-laser by about an order of magnitude. Possible reasons for the low lasing efficiency and the high lasing threshold will be discussed.