Critical exponents for the metal-insulator transition

Critical Exponents for the Metal–Insulator Transition in Disordered Systems

The critical exponents of the metal–insulator transition in disordered systems have been the subject of much published work containing often contradictory results. Values ranging between 1/2 and 2 can be found even in the recent literature. In this paper the results of a long term study of the transition are presented. The data have been calculated with sufficient accuracy (0.2%) that the calcu...

Critical exponents for the metal-insulator transition of 70Ge:Ga in magnetic fields

We have measured the electrical conductivity of nominally uncompensated 70Ge:Ga samples in magnetic fields up to B = 8 T at low temperatures (T = 0.05− 0.5 K) in order to investigate the metal-insulator transition in magnetic fields. The values of the critical exponents in magnetic fields are consistent with the scaling theories.

Critical fidelity at the metal-insulator transition.

Using a Wigner Lorentzian random matrix ensemble, we study the fidelity, F(t), of systems at the Anderson metal-insulator transition, subject to small perturbations that preserve the criticality. We find that there are three decay regimes as perturbation strength increases: the first two are associated with a Gaussian and an exponential decay, respectively, and can be described using linear res...

Critical properties of the metal-insulator transition in anisotropic systems

We study the three-dimensional Anderson model of localization with anisotropic hopping, i.e., weakly coupled chains and weakly coupled planes. In our extensive numerical study we identify and characterize the metal-insulator transition by means of the transfer-matrix method. The values of the critical disorder Wc obtained are consistent with results of previous studies, including multifractal a...

Critical behavior of Si:P at the metal-insulator transition.