Optical and thermal properties of crystalline Tb: KLu(WO 4) 2

Abstract

A single crystal of Tb: KLu(WO 4) 2 with dimensions of 40 mm × 40 mm × 18 mm has been grown by the top-seeded solution growth (TSSG) method. The color of the crystal is brown. Absorption and fluorescence spectra were measured at room temperature. The measured specific heat is a little lower than that of Yb: KLW (0.365 J/g K) at 90 °C. The measured mean linear coefficients of thermal expansion are α a = 17.1643 × 10 − 6 K − 1 , α a ⁎ = 14.0896 × 10 − 6 K − 1 , α b = 8.7938 × 10 − 6 K − 1 , α c = 23.1745 × 10 − 6 K − 1 , α c ⁎ = 20.2866 × 10 − 6 K − 1 . The results indicate that the crystal has a large anisotropy. The refractive index was measured.