Spectral properties of nearly free and strongly correlated one-dimensional electrons

Abstract

Abstract One-dimensional metals are described as Luttinger liquids. Their spectral properties are characterized by at least three dispersing features: charge and spin excitations and at least one shadow band. Their origins are explained in detail in terms of charge–spin separation, anomalous power-law correlations, and hybridization of electronic states. In one-dimensional Mott and Peierls insulators and superconductors, the spectral function has similar features above the charge or spin gaps, but under some circumstances, one of the peaks may be cut off or masked alltogether. There are no anomalous dimensions in the gapped channel close to the gap edge. The shadow bands are significantly strengthened. The spectral weight of nearly-free electrons in one-dimensional superlattices is peaked on the band dispersion in the extended zone scheme, and shadow bands with reduced intensity trace out the periodic zone scheme. Motivated by recent experiments on the one-dimensional Peierls system (TaSe 4 ) 2 I, we discuss the doping of a Peierls ladder and calculate the spectral properties of such a system. They are in good agreement with experiments.