Arguments are presented that the T=0 conductance G of a disordered electronic system depends on its length scale L in a universal manner. Asymptotic forms are obtained for the scaling function β(G)=dlnG/dlnL, valid for both G≪Gc≃e2/ℏ and G≫Gc. In three dimensions, Gc is an unstable fixed point. In two dimensions, there is no true metallic behavior; the conductance crosses over smoothly from logarithmic or slower to exponential decrease with L.
URL:
http://link.aps.org/doi/10.1103/PhysRevLett.42.673
DOI:
10.1103/PhysRevLett.42.673
*Also at Bell Laboratories, Murray Hill, N. J. 07974.
†On leave from Indian Institute of Technology, Kanpur, India.