The ordinary and extraordinary refractive index of two samples of sapphire, which differed in the way each was grown, was measured. The measurements were made over a wavelength range of 477–701 nm and a temperature range of 20–295 K. A three-term Sellmeier dispersion equation was fit to the data to permit refractive-index interpolation within several parts in 104. The data of index versus temperature were fit to a model and the results of dn/dT versus temperature are given along with certain physical constants that were extracted from the model.
© 1993 Optical Society of America
Original Manuscript: March 3, 1992
Published: May 1, 1993
A. C. DeFranzo and B. G. Pazol, "Index of refraction measurement on sapphire at low temperatures and visible wavelengths," Appl. Opt. 32, 2224-2234 (1993)