The three-dimensional Anderson model of localization with binary random potential

We study the three-dimensional two-band Anderson model of localization and compare our results to experimental results for amorphous metallic alloys (AMA). Using the transfer-matrix method, we identify and characterize the metal-insulator transitions as functions of Fermi level position, band broadening due to disorder and concentration of alloy composition. The appropriate phase diagrams of regions of extended and localized electronic states are studied and qualitative agreement with AMA such as Ti-Ni and Ti-Cu metallic glasses is found. We estimate the critical exponents nu_W, nu_E and nu_x when either disorder W, energy E or concentration x is varied, respectively. All our results are compatible with the universal value nu ~ 1.6 obtained in the single-band Anderson model.Comment: 9 RevTeX4 pages with 11 .eps figures included, submitted to PR

The MCLIB library: New features

This report describes the philosophy and structure of MCLIB, A Fortran library of Monte Carlo subroutines which has been developed to test designs of neutron scattering instruments. Emphasis is placed on new features added to the library since the previous presentation of MCLIB at ICANS-XIII in October, 1995. These new features include toroidal mirrors, writing and reading source files, splitting and banking of histories, and a Maxwellian probability distribution. The only change of a program structure has been to include charge and polarization vector in the description of a particle. The latest release of the source code and documentation may be obtained by anonymous ftp. Work is also continuing on a more friendly web-based user interface, and user input is requested for additional features to be added to the library