Observation of nonlinear lasing χ⁽³⁾-effects in highlytransparent nanocrystalline Y₂O₃ andY₃Al₃O₁₂ ceramics

Multi-wavelength nonlinear parametric χ (3) -effects were observed in highly transparent Y 2 O 3 and Y 3 Al 5 O 12 nanocrystalline ceramics under picosecond pumping at 300 K. All recorded Stokes and anti-Stokes components in the visible and near IR were identified and attributed to the stimulated Raman scattering active vibration modes of these novel optical and laser-host crystalline materials. For both materials, the steady-state first-Stokes Raman gain coefficient was estimated at a wavelength of around 1 μm.