Optical and thermal properties of crystalline Tb: KLu(WO_4)_2

摘要

A single crystal of Tb: KLu(WO_4)_2 with dimensions of 40 mm x 40 mm x 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℃. The measured mean linear coefficients of thermal expansion are α_a= 17.1643 x 10~(-6) K~(-1) α_a~* = 14.0896 x 10~(-6)K~(-1), α_b=8.7938 x 10~(-6)K~(-1), α_c=23.1745 x10~(-6)K~(-1),α_c~*=20.2866 x 10~(-6) K~(-1). The results indicate that the crystal has alarge anisotropy. The refractive index was measured.