The Temperature Changes of Refractive Indices and Thickness of Doped Triglycine Sulfate Crystals

The temperature dependences of the optical path difference δΔi and the relative changes in the thickness δli/l of TGS crystals doped with L-threonine are studied. The temperature dependences of the relative changes in the refractive indices δni/(n – 1), coefficients of anisotropy for refractive indices, and linear expansion have been calculated. Characteristic minimum has been detected on these curves near the phase transition temperature.