Fluctuation-enhanced electric conductivity in electrolyte solutions

In this letter we analyze the effects of an externally applied electric field on thermal fluctuations for a fluid containing charged species. We show in particular that the fluctuating Poisson-Nernst-Planck equations for charged multispecies diffusion coupled with the fluctuating fluid momentum equation, result in enhanced charge transport. Although this transport is advective in nature, it can macroscopically be represented as electrodiffusion with renormalized electric conductivity. We calculate the renormalized electric conductivity by deriving and integrating the structure factor coefficients of the fluctuating quantities and show that the renormalized electric conductivity and diffusion coefficients are consistent although they originate from different noise terms. In addition, the fluctuating hydrodynamics approach recovers the electrophoretic and relaxation corrections obtained by Debye-Huckel-Onsager theory, and provides a quantitative theory that predicts a non-zero cross-diffusion Maxwell-Stefan coefficient that agrees well with experimental measurements. Finally, we show that strong applied electric fields result in anisotropically enhanced velocity fluctuations and reduced fluctuations of salt concentrations.Comment: 12 pages, 1 figur

Colossal Electric Conductivity in Ag-defect Ag5Pb2O6

Bystroem-Evers compound Ag5 Pb2O6 has been annealed at 500-540 K under flow of electric current which results in a textured structure and anisotropic colossal electric conductivity (> 10^9 ohm-1cm-1) between 210-525 K. The related physical properties are primarly governed by dissociation of Ag from c-axis channels and lattice strains which in turn depend upon electric current.Comment: 13 pages, 7 figure

Imperfect nesting and transport properties in unconventional density waves

We consider the effect of imperfect nesting in quasi-one dimensional unconventional density waves. The phase diagram is very close to those in a conventional DW. The linear and non-linear aspects of the electric conductivity are discussed. At T=0 the frequency dependent electric conductivity develops a small dip at low frequencies. The threshold electric field depends strongly on the imperfect nesting parameter, allowing us to describe the measured threshold electric field in the low temperature phase of the quasi-two dimensional organic conductor, alpha-(BEDT-TTF)_2KHg(SCN)_4 very well.Comment: 9 pages, 9 figure

Investigation of electrical conductivity in amorphous semiconductors Semiannual report

Electric conductivity and electron transport mechanisms in amorphous semiconductor