The characterization of pure and niobium-doped crystals of strontium titanate using Hall, electrical conductivity, and optical absorption data

A description is given of the heat treatment, under controlled conditions, of crystals of strontium titanate, both pure and niobium-doped, and of the effect of this treatment on the defect states in this material. Our analysis is based on evaluation of the results of electrical conductivity and Hall effect measurements, and those of optical absorption.