Influence of Various Dopants on Electrical and Optical Properties of Amorphous Ge_0.42 S_0.58

Abstract

Electrical and optical properties have been studied on Ge_0.42 S_0.58 glasses containing a series of elements with different valencies. The glass containing a small amount of Cu or Ag brings about a large increase in the d. c. conductivity with a decrease of the activation energy, and brings about a slight decrease of the optical gap and an increase of the steepness of the optical absorption edge. These results are explained by the decrease of a range of the localized states due to a reduction of disorder in the glass-structure. The glasses containing Zn, Cd, Al, In or I have not shown such behaviors. These elements are considered to tend to be incorporated in the glass-network without reducing the disorder in the parent glass.