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The self averaging properties of conductance $g$ are explored in random resistor networks with a broad distribution of bond strengths $P(g)simg^{mu-1}$. Distributions of equivalent conductances are estimated numerically on hierarchical lattices as a function of size $L$ and distribution tail parameter $mu$. For networks above the percolation threshold, convergence to a Gaussian basin is always the case, except in the limit $mu$ --> 0. A {it disorder length} $xi_D$ is identified beyond which the system is effectively homogeneous. This length diverges as $xi_D sim |mu|^{- u}$ ($ u$ is the regular percolation correlation length exponent) as $mu$-->0. This suggest that exactly the same critical behavior can be induced by geometrical disorder and bu strong bond disorder with the bond occupation probability $p$<-->$mu$. Only lattices at the percolation threshold have renormalized probability distribution in a {it Levy-like} basin. At the threshold the disorder length diverges at a vritical tail strength $mu_c$ as $|mu-mu_c|^{-z}$, with $z=3.2pm 0.1$, a new exponent. Critical path analysis is used in a generalized form to give form to give the macroscopic conductance for lattice above $p_c$.
We consider the isotropic-to-nematic transition in liquid crystals confined to aerogel hosts, and assume that the aerogel acts as a random field. We generally find that self-averaging is violated. For a bulk transition that is weakly first-order, the
We study sample-to-sample fluctuations in a critical two-dimensional Ising model with quenched random ferromagnetic couplings. Using replica calculations in the renormalization group framework we derive explicit expressions for the probability distri
A linear unsaturating magnetoresistance at high perpendicular magnetic fields, together with a quadratic positive magnetoresistance at low fields, has been seen in many different experimental materials, ranging from silver chalcogenides and thin film
We study the effective resistance of small-world resistor networks. Utilizing recent analytic results for the propagator of the Edwards-Wilkinson process on small-world networks, we obtain the asymptotic behavior of the disorder-averaged two-point re
We investigate, by means of extensive Monte Carlo simulations, the magnetic critical behavior of the three-dimensional bimodal random-field Ising model at the strong disorder regime. We present results in favor of the two-exponent scaling scenario, $