The critical behavior of magneto-transport in a percolating medium in the presence of a magnetic field H of arbitrary strength is discussed. A discrete network model is used to solve the problem exactly for a three-dimensional Sierpiński gasket fractal. We find that there is strong magneto-resistance in this model. We also find a new scaling behavior of the effective ohmic resistivity ρ(e)(L, H) as function of the size L of the fractal and magnetic field H. In a percolating metal-insulator mixture, the resistivity ratio with and without a field ρ(e)(p, H) ρ(e)(p, 0) is predicted to saturate at the percolation threshold p→pc at a value ∼ H0.415.
|Number of pages||5|
|Journal||Physica A: Statistical Mechanics and its Applications|
|State||Published - 15 Dec 1992|