Electrical conductivity above the superconducting transition temperature in quasi-one-dimensional conductors

The parallel (to the chain axis) excess conductivity due to superconducting fluctuation above the transition temperature T sub(c) is calculated. The phase representation of the BGD model with Josephson type interchain interaction is used. The excess conductivity σ' behaves as epsilon sup(-1/2) (epsilon = (T - T sub(c)/T sub(c))) near the transition temperature. At higher temperatures σ' behaves as (T/T sub(c))sup(-3+2eta sub(-)), where eta sub(-) = √(1 + a tilde)/(1 - a tilde), a tilde = (g2 - g1/2)/(πv sub(F)) and g2(g1) is the coupling constant of the intrachain forward (backward) scattering of the BGD model. Also a diagram technic in treating the phase Hamiltonian is described. (author)