Growth, Spectroscopic Characteristics, and Laser Performance of Nd3+-Doped Lu x Y3-xGa5O12Composite Laser Crystals

Abstract Rare-earth-ion-doped disordered crystals are an effective route to spectral broadening. In this study, high-quality Nd:Lu(x)Y(3-x)Ga5O12 composite laser crystals were grown using the Czochralski method. The crystal dimensions were Ø30 × 90 mm2, and the structure of the Nd:LuYGG crystal was characterized using X-ray diffraction (XRD), XRC, scanning electron microscope (SEM), and ICP-MS. Raman spectroscopy was performed to identify vibrational modes, with the maximum phonon energy determined to be 762.1 cm–1. Absorption, fluorescence spectra, and fluorescence lifetime were measured, revealing that the Nd:LuYGG crystal exhibits pronounced inhomogeneous broadening. Spectroscopic parameters were calculated based on Judd-Ofelt theory. Furthermore, laser experiments generated triple-wavelength outputs at 1058, 1060, and 1066 nm, where a maximum output power of 5.47 W and a slope efficiency of 23.0% were achieved. The broad spectral bandwidth and multiwavelength output demonstrate that the Nd:LuYGG crystal is a material with significant potential for applications in terahertz radiation, tunable lasers, and ultrashort-pulse laser systems.