LiNa₅Mo₉O₃₀: Crystal Growth, Linear, and Nonlinear Optical Properties

We report on the crystal growth, linear, and nonlinear optical properties of LiNa 5 Mo 9 O 30 . The refractive indices were measured, and a very large birefringence of 0.2545 at 450.2 nm was determined. In addition, calculated phase-matching curves indicate that LiNa 5 Mo 9 O 30 can achieve noncritical type I and type II phase-matching (NCPM) for incident 1064 nm radiation. Maker fringe measurements, to determine individual nonlinear optical coefficients, were also performed on the crystals resulting in d 31 = 1.4 pm/V, d 32 = 4.3 pm/V, and d 33 = 1.1 pm/V. The laser damage threshold (LDT) is around 1.2 GW/cm 2 at 1064 nm using a 6 ns Nd:YAG laser operating at 5 Hz. The quality of the crystals was measured by high resolution X-ray diffraction rocking curve measurements that revealed a full width at half-maximum (fwhm) of 59″ from the (001) reflection. The absorption edge was determined to be 357 nm, with transmission up to 5.26 μm. Our results indicate that single crystal LiNa 5 Mo 9 O 30 is an excellent polarizer as well as second-order nonlinear optical material.