Measurements of the complex dielectric constant (ε′ + iε″) on a series on NbC-KCl composites in a wide range of concentrations are performed as a function of φ (the volume fraction of the 1–3 μm NbC grains) at frequencies of 102, 103, 104 and 105 Hz. Frequency scaling of ε = ε′ +...

Measurements of χ′ and χ″ have been made at 36.7 Hz, using two dual phase lock-in amplifiers, on a series of NbC-KCl composites. The measurements are made, between 4.5 and 12 K, as a function of φ (the volume fraction of the 1–3 μm NbC grains) between 0.0 and 0.40, and in AC fields...

Resistivity ϱxx and Hall resistivity ϱxy were measured as functions of the magnetic field, temperature, and the metal volume fraction x, on a series of percolating NiSiO2 granular films. At 5 K, the data for the metallic samples were fitted to power law dependencies of the forms, ϱxx ∝...

A large, by a factor of ≈103−104, enhancement of Hall effect in cosputtered magnetic granular metals such as (NiFe)x-(SiO2)1−x near the metal-insulator transition has been termed giant Hall effect (GHE). It is associated with a high resistivity which increases slowly with decreasing...

Compressed discs made from graphite and, its mechanical but not electrical isomorph, boron nitride, as well as graphite-boron nitride powders, undergoing compression, are nearly ideal continuum percolation systems; as the ratio of their conductivities is 10−18 and the scatter of the...

Granular Al-Ge films, just on the metallic side of the critical volume fraction φc (50.7% Al), are found to have critical fields in excess of 1.5T at 0.47 K due to the fine granular nature of the Al. In barely insulating films where φc − φ 2.2% (φ is the volume fraction of aluminum),...

Thermoelectric power (Seebeck coefficient) measurements at room temperature have been made on composite Al-Ge films for aluminum volume fractions ranging from 20% to 100%. The critical metallic concentration φc at the metal-insulator transition is about φc⋍55%. These measurements were...

The electrical conductivity (σ), the thermal conductivity (λ) and the permeability (μ) are given as functions of the volume fractions for a series of sintered nickel samples. It is shown that σ, λ and μ data can all be fitted to a single equation with the same two morphology parameters ƒc...

The construction and the measurement of the conductivity of a series of two-dimensional dual media is described. The conductivity results are shown to obey both the defining relationship for dual media and a recently proposed general effective-media (GEM) equation, with two morphology...

The metal-insulator transition in composite Al-Ge films has been extensively studied experimentally. Using the superconducting properties of percolating clusters composed of small aluminum grains in the presence of a magnetic field, the critical metallic volume fraction φc(sc) for the...