LEVEL CURVATURE AND METAL-INSULATOR-TRANSITION IN 3D ANDERSON MODEL

The level curvature in the Anderson model on a cubic lattice is numeri cally investigated as an indicator of the metallic-insulator transitio n. It is shown that the mean curvature obeys a scaling law in the whol e range of the disorder parameter. In the metallic regime, the distrib ution of rescaled curvatures is found to be well described by a formul a proposed by Zakrzewski and Delande [1] for random matrices, implying a relation similar to that by Thouless. In the localized regime the d istribution of curvatures is approximated by a log-normal distribution .