Novel Laser Crystal Nd:LiY(MoO4)2: Crystal Growth, Characterization, and Orthogonally Polarized Dual-Wavelength Laser

The orthogonal polarized dual-wavelength laser has attracted increasing attention due to its unique applications in spectral analysis, differential radar, terahertz, etc. In this paper, the Nd-doped LiY(MoO4)2 (LYMO) crystal with a disordered structure is selected as a laser gain medium to obtain the dual-wavelength laser. The fluorescence spectra of the Nd:LYMO crystal show obvious polarization anisotropy, which is caused by the anisotropic lattice field. The π- and σ-polarized stimulated emission cross-sections at 1061 and 1068 nm are calculated to be 17.5 × 10–20, 8.7 × 10–20, 9.1 × 10–20, and 20.6 × 10–20 cm2, respectively. The lasers operating at 1061 and 1068 nm are obtained using c- and a-cut Nd:LYMO crystals, respectively. More importantly, a 1061 and 1068 nm orthogonally polarized dual-wavelength laser is also successfully designed and achieved using a 45°-cut Nd:LYMO crystal; the corresponding optical-to-optical conversion efficiency and slope efficiency are 27.9 and 31.7%, respectively. Our research confirms that the Nd:LYMO crystal can achieve efficient orthogonally polarized dual-wavelength laser output, which would have potential applications in differential frequency and terahertz fields.