Investigation of localized states in cadmium zinc telluride crystals by scanning photodielectric spectroscopy

We discuss a method of scanning photodielectric spectroscopy of crystals which is based on the measurements of small increments of the real Δε\´ and imaginary Δε" parts of dielectric permittivity, which are induced by a smooth variation of the photoexcitation wavelength. The spectral dependences of both parts of the dielectric constant upon the light wavelength were presented in the complex plane. Application of this method on Cd_0.9Zn_0.1Te crystals showed a possibility of determining the energy position of the localized states generated in the forbidden zone by the intrinsic structure defects.