TEMPERATURE-DEPENDENCE OF THE ELECTRICAL-CONDUCTIVITY OF AMORPHOUS VXSI1-X

We present results for the temperature dependence of electrical conductivity for amorphous VxSi1-x alloys. The alloys investigated span the composition range from x=0.5 to 0.1. For the alloys with more than 20 at. % V, the temperature dependence could be successfully fitted with use of the theories of quantum interference effects, and values for the spin-orbit and inelastic scattering rates are extracted from the fits. As the concentration of V is decreased, there is evidence for a metal-insulator transition seen at around 15 to 13 at. % V. The temperature dependence of the conductivity is surprisingly similar for all the alloys on the metallic side of the transition, showing a clear T1/2 dependence at the lowest temperatures while the insulating V0.1Si0.9 alloy shows evidence for variable-range-hopping conduction. The V0.13Si0.87 alloy, which is right at the transition, exhibits an unusual temperature dependence. The sample is metallic and seems to follow a T1/3 dependence at low temperatures. © 1990 The American Physical Society.