PURE AND ND-3+-ION, PR-3+-ION DOPED TRIGONAL ACENTRIC LABGEO5 SINGLE-CRYSTALS - NONLINEAR OPTICAL-PROPERTIES, RAMAN-SCATTERING, SPECTROSCOPY, CRYSTAL-FIELD ANALYSIS, AND SIMULATED EMISSION OF THEIR ACTIVATORS

Complex spectral investigations are made on new Nd3+- and Pr3+-doped and pure nonlinear-laser trigonal LaBGeO5 crystals. Raman spectra and nonlinear optical properties are studied including second harmonic generation, absorption, and luminescence spectra, which allow to determine the energy of Stark levels of the activator ions, luminescence-intensity characteristics, and pulse stimulated-emission parameters of Nd3+ ions at two intermanifold 4F3/2 --> 4I11/2 and 4F3/2 --> 4I13/2 channels as well as of Pr3+ ions at the visible 3P0 --> H-3(6) transition. A preliminary theoretical analysis is made of the crystal field at activator ions using a new many-electron semiempirical method. All registered induced transitions are identified. LaBGeO5:Nd3+ is shown as a promising material for self-frequency doubled laser.