Anomalous scaling and spin-charge separation in coupled chains

TL;DR

This paper investigates how Coulomb interactions influence electronic behavior in coupled metallic chains, revealing a transition from Luttinger to Fermi liquid states and explaining experimental anomalies in quasi-one-dimensional conductors.

Contribution

It demonstrates that Coulomb interactions induce a Luttinger liquid state at zero inter-chain hopping and a Fermi liquid at finite hopping, with a detailed analysis of the intermediate regime.

Findings

Large anomalous exponent $oldsymbol{eta_{cb}}$ explained by Coulomb interactions.

Transition from Luttinger to Fermi liquid with increasing inter-chain hopping.

Relevance to photoemission data and high-temperature superconductors.

Abstract

We use a bosonization approach to show that the three dimensional Coulomb interaction in coupled metallic chains leads to a Luttinger liquid for vanishing inter-chain hopping $t_{\bot}$, and to a Fermi liquid for any finite $t_{\bot}$. However, for small $t_{\bot} \neq 0$ the Greens-function satisfies a homogeneity relation with a non-trivial exponent $\gamma_{cb}$ in a large intermediate regime. Our results offer a simple explanation for the large values of $\gamma_{cb}$ inferred from recent photoemission data from quasi one-dimensional conductors and might have some relevance for the understanding of the unusual properties of the high-temperature superconductors.