Renormalization group analysis of electrons near a Van Hove singularity.

TL;DR

This paper uses renormalization group methods to analyze how electron interactions near a Van Hove singularity lead to marginal behavior and anisotropic superconductivity, with the chemical potential pinned near the singularity in hole-doped systems.

Contribution

It provides a renormalization group analysis of electron interactions near Van Hove singularities, revealing marginal behavior and superconductivity characteristics.

Findings

Chemical potential pinned near singularity in hole-doped systems

Emergence of anisotropic superconductivity

Marginal behavior from leading divergences in perturbation theory

Abstract

A model of interacting two dimensional electrons near a Van Hove singularity is studied, using renormalization group techniques. In hole doped systems, the chemical potential is found to be pinned near the singularity, when the electron-electron interactions are repulsive. The RG treatment of the leading divergences appearing in perturbation theory give rise to marginal behavior and anisotropic superconductivity.