Transport properties of Ge-Ga-S glass doped by praseodymium

The temperature dependencies of direct electrical conductivity and temperat ure and frequency dependencies of permittivity of prepared sulphide glasses doped by praseodymium ions (Ge-25 Ga-10.x, Pr-x S-65, x = 1000 wt. ppm) we re measured. The results indicate the existence of one conductivity mechani sm with activation energy 0.91 eV up to the temperature 360 degrees C. The dependencies of electrical modulus M" versus M' as well as the frequency de pendencies M" versus f show that the glass has monophase structure and is v ery homogeneous with the presence of only one relax time. The glass exhibit s new relax time distribution indicating the formation of new structure whe n it was tempered up to 380 degrees C, that means just below T-g similar to 400 degrees C.