New scandium borates RxLayScz(BO3)4 (x+y+z=4, R=Sm, Tb): synthesis, growth, structure and optical properties

Abstract Herein we report the growth of new RxLayScz(BO3)4 (x + y+z = 4, R = Sm, Tb) crystals with large second-harmonic generation (SHG) responses. The obtained compounds, grown from eutectic LiBO2-LiF flux by the TSSG method, crystallize in the space group P321 with the cell parameters a = 9.800(15) A and c = 7.9565(7) A for Sm0.34La0.68Sc2.98(BO3)4 and a = 9.7976(7) A and c = 7.9567(12) A for Tb0.23La0.77Sc3(BO3)4. These crystalline materials also exhibit luminescent properties related to the optical transitions of Tb3+ and Sm3+; specifically, Tb0.23La0.77Sc3(BO3)4 shows a strong green emission that is dominated by the 5D4 to 7F5 transition. The studied crystals’ SHG intensities were higher than those of KDP crystals, revealing their potential uses in various nonlinear optics applications.