Kramers–Kronig relations in modulation polarimetry diagnostics of glass-ceramics

It has been found that, in an aluminosilicate glass-ceramic sample cut from a massive ingot, there is a correlation of the residual stress with the temperature gradient. The magnitude and coordinate dependence of the stress along the temperature gradient have been determined from the stress-induced linear birefringence measured by the modulation polarimetry technique. Its functional relationship has been established in the form of the Poisson equation with the heterogeneity of the composition due to the preparation conditions. It has been shown that, in the absence of a temperature gradient, the birefringence and dichroism related by the Kramers–Kronig relation play the role of thermodynamic variables.