Scaling of the Conductivity with Temperature and Uniaxial Stress in Si:B at the Metal-Insulator Transition

Using uniaxial stress $S$ to tune Si:B through the metal-insulator transition at a critical value $S_c$, we find the dc conductivity at low temperatures shows an excellent fit to the scaling form $\sigma (S,T){=AT}^{x}f\left[\right({S-S}_c\left){/T}^y\right]$ on both sides of the transition. The scaling functions yield reliable determinations of the temperature dependence of the conductivity in the metallic and insulating phases in the critical region.