Linear optical and thermo-physical properties of polar K3B6O10Cl crystal

Single crystal of K 3 B 6 O 10 Cl with size of 35 mm × 35 mm × 11 mm was grown by the TSSG method for the first time. In the crystal growth process, the cooling rate, the rotating speed and seed direction have been investigated. Based on the measurement of refractive-index from UV to NIR region, the limit of type-I phase matching second harmonic generation wavelength was calculated to be 272 nm, which is a little shorter than that of LiB 3 O 5 (277 nm). Thermal properties including specific heat, thermal diffusion and thermal conductivity were performed on the crystal. In addition, polarization measurements demonstrate that although K 3 B 6 O 10 Cl is polar, the material is not ferroelectric.