Abstract

Self-frequency doubling (SFD) lasers with emission in the green range have a tremendous number of applications. An efficient SFD material should exhibit properties as high damage threshold, high emission cross section at laser wavelength, good absorption at pumping and low at second harmonic wavelengths, congruent melting, high nonlinearity, non-hygroscopicity and phase matching achieved at room temperature, etc. Among the available laser crystals with SFD properties, Nd³⁺:GdCa₄O(BO)₃ (Nd:GdCOB) single crystal has attracted great attention due to its excellent properties, except for its thermal conductivity [1, 2]. SFD was achieved in Nd:GdCOB, in principal plane XY or out of principal planes. However, efficient SFD in principal plane ZX (d_eff~1.1pm/V), with higher nonlinearity than XY plane, could be achieved, if the polarization of the emitted fundamental wave is along Y axis [2]. Recent papers discovered that Y polarized emission at 1.06 μm is observed in co-doped Nd³⁺, Lu3⁺:GdCa₄O(BO₃)₃ (Nd:GdLuCOB) single crystal [3].

© 2015 IEEE