Sharp Metal-Insulator Transition in a Random Solid

Abstract

Zero-temperature metallic conductivities have been measured above and below Mott's minimum value σ_(min) in bulk crystals of P-doped Si. Conductivities below σ_(min) increase by over 10^3 as the density is raised by less than 1%, and do not rule out a discontinuous transition. However, over a wider density range the data can be fitted with a scaling form with a characteristic length that tends to diverge with the same exponent in the metal and insulator.

Files

Additional details