Coherence-Incoherence Transition Between Fermi and Luttinger liquids

TL;DR

This paper investigates the stability and transition conditions between Fermi and Luttinger liquids in anisotropic quasi-one-dimensional metals, highlighting how interchain coupling and spin-charge separation influence quasiparticle existence.

Contribution

It introduces a model of coupled spin-1/2 Luttinger liquids to analyze the coherence-incoherence transition and the effects of lattice coordination and spin-charge separation.

Findings

Luttinger liquid stability increases as lattice coordination decreases.

Some Luttinger liquid features can persist in the Fermi liquid phase.

Interchain hopping influences the transition between Fermi and Luttinger liquids.

Abstract

We consider conditions for existence of fermionic quasiparticles in a strongly anisotropic quasi-one-dimensional metal. The adopted model is a model of chains of spin-1/2 Luttinger liquid coupled by small interchain hopping. It is shown that the Luttinger liquid becomes more stable with decrease of the lattice coordination number. It is also shown that with a significant spin-charge separation some Luttinger liquid features may persist in the Fermi liquid phase.