Critical exponents of a multicomponent anisotropic t-J model in one dimension

TL;DR

This paper analyzes a one-dimensional anisotropic multicomponent t-J model, revealing its critical behavior, excitation spectrum, and effective mass, with implications for understanding strongly correlated fermionic systems.

Contribution

It introduces and solves a new anisotropic multicomponent t-J model using Bethe ansatz, highlighting its critical properties and excitation modes.

Findings

Model exhibits $2S$ massive modes and one gapless excitation.

Critical behavior follows a $c=1$ conformal field theory with variable exponents.

Effective mass of charge carriers is significantly enhanced compared to isotropic case.

Abstract

A recently presented anisotropic generalization of the multicomponent supersymmetric $t-J$ model in one dimension is investigated. This model of fermions with general spin-$S$ is solved by Bethe ansatz for the ground state and the low-lying excitations. Due to the anisotropy of the interaction the model possesses $2S$ massive modes and one single gapless excitation. The physical properties indicate the existence of Cooper-type multiplets of $2S+1$ fermions with finite binding energy. The critical behaviour is described by a $c=1$ conformal field theory with continuously varying exponents depending on the particle density. There are two distinct regimes of the phase diagram with dominating density-density and multiplet-multiplet correlations, respectively. The effective mass of the charge carriers is calculated. In comparison to the limit of isotropic interactions the mass is strongly enhanced in general.