Spin Gap Fixed Points in the Double Chain Problem

TL;DR

This paper investigates the fixed points in coupled Hubbard chains where spin excitations become gapped and singlet pairing dominates, using bosonization and renormalization group analysis.

Contribution

It introduces a detailed analysis of spin gap fixed points in double chain systems through bosonization and RG flow techniques.

Findings

Identification of fixed points with all spin excitations gapped

Singlet pairing as the dominant instability at these fixed points

Application of bosonization to analyze weakly coupled Hubbard chains

Abstract

Applying the bosonization procedure to weakly coupled Hubbard chains we discuss the fixed points of the renormalization group flow where all spin excitations are gapful and a singlet pairing becomes the dominant instability.