Temperature coefficients of the indices of refraction and of the birefringence in cadmium sulphide

Measurements are reported of the temperature dependence of the indices of refraction and of the birefringence of CdS. The measurements were performed at 10.3 μm wavelength in the room temperature range with a CO2 laser with light power of the order of 1 W passing through the sample. The values of the birefringence, indices of refraction, and optical absorption were also verified. The results are δe = (1/ne)(dne/dT) = (27.8 ± 0.2) × 10−6 (°C)−1, δ0 = (1/n0)(dn0/dT) = (26.8 ± 0.3) × 10−6 (°C)−1, Λ = d(ne − n0)/dT = (3.07 ± 0.12) × 10−6 (°C)−1, Δn = 0.011 ± 0.001, ne = 2.245 ± 0.017, n0 = 2.227 ± 0.017, and α = 0.045 cm−1.