Near-infrared and upconversion properties of neodymium-doped RE0.8La0.2VO4 (RE = Y, Gd) single-crystal fibres grown by the laser-heated pedestal growth technique

Neodymium-doped Y0.8La0.2VO4 and Gd0.8La0.2VO4 single-crystal fibres were successfully grown by the laser-heated pedestal growth (LHPG) technique.. The fibres were completely transparent and no dark inclusions were observed by optical microscopy. In the characterization process, microprobe Raman, optical absorption, fluorescence, lifetime, and gain-excited state absorption spectra were investigated in addition to upconversion measurements. The fibres' structural and spectroscopic properties are very similar to those of YVO4 and GdVO4 bulk laser crystals, with the advantageous characteristic of broadened spectral linewidths that facilitate the pumping of the 1064 nm. emission by a diode laser. These fairly new crystal compositions, that can be grown in fast and economical processes, are potential candidates for use as compact laser-active media.