The tetragonal germanates Sr 2 MgGe 2 O 7 and Ba2ZnGe2O7 were found to be attractive, simultaneously χ (2) -and χ (2) -active nonlinear multifunctional crystals. Their basic optical properties were investigated and numerous nonlinearlaser effects, among them SRS, more than one-octave Stokes and anti-Stokes combs, SHG, THG, SFG, and efficient cascaded self-conversion (χ (3) ↔ χ (2) )-generation were observed in the visible and UV range. All recorded nonlinear-lasing components were identified and attributed to SRS-promoting vibration modes of the studied crystals.Example of a color image of conical multi-wavelength antiStokes generation ("anti-Stokes rainbow")

Non‐centrosymmetric tetragonal crystalCa2MgSi2O7:Nd3+(Na+) with incommensurately modulated melilite‐type structure is presented as a new laser crystal. By LD and Xe‐flashlamp pumping its CW and free‐running pulsed stimulated emission of the 4F3/2 → 4I11/2 generation channel of Nd3+ lasant ions was excited. (© 2010 by Astro Ltd., Published exclusively by WILEY‐VCH Verlag GmbH & Co. KGaA)

Efficient room-temperature Stokes and anti-Stokes χ (3) -nonlinear picosecond generation, which spans more than two octaves (≈ 23012 cm −1 ) has been observed in a natural crystal of orthorhombic SrSO 4 (celestine). All recorded lasing lines in the visible and near-IR regions are identified and attributed to its SRS-promoting vibration mode ω SRS ≈ 999 cm −1 .Example of a color image of the spatially distributed components of conical parametric multi-wavelength anti-Stokes RFWM lasing of a single crystal of SrSO 4