Photoconduction in Pb-Ge-Se semiconducting glasses exhibiting carrier typereversal

Photoconductivity properties of PbxGe42-xSe58 (0 less than or equal to x le ss than or equal to 20) and Pb20GeySe80-y (17 less than or equal to y less than or equal to 24) semiconducting chalcogenide glasses have been studied and reported. Both these systems are known to exhibit carrier type reversal from p-type to n-type nt certain critical compositions. It is shown that c arrier type reversal gets reflected clearly ill photoconductivity measureme nts. Temperature dependence of photoconductivity properties has also been i nvestigated.. The results are analyzed on the basis of existing models.