High temperature structural instability in quasi-one-dimensional conductors

Abstract

The most important steps on the way from the simple tight-binding band approximation to the simple fluctuation theory for high-temperature quasi-one-dimensional conductors are discussed. The tight-binding formulation is reviewed with particular emphasis on the strong anisotropic effects. This formulation is then set into the context of the many-body theory. It appears that at sufficiently high temperatures the parquet degeneracy of the many-body theory might break. The ensuing simplification leads to a single-order parameter phase transition theory which is reviewed and completed in respect of the problem of quasi-one-dimensional conductors.