Is charge order induced near an antiferromagnetic quantum critical point?

TL;DR

This study uses quantum Monte Carlo simulations to explore how charge order and superconductivity interact near an antiferromagnetic quantum critical point, revealing symmetry effects and phase transitions relevant to cuprate superconductors.

Contribution

It demonstrates the emergent SU(2) symmetry linking charge order and superconductivity and shows how deviations from particle-hole symmetry influence their competition.

Findings

Emergent SU(2) symmetry at particle-hole symmetry

Charge order is suppressed by superconductivity

Charge order wave-vector shifts from diagonal to axial

Abstract

We investigate the interplay between charge order and superconductivity near an antiferromagnetic quantum critical point using sign-problem-free Quantum Monte Carlo simulations. We establish that, when the electronic dispersion is particle-hole symmetric, the system has an emergent SU(2) symmetry that implies a degeneracy between $d$-wave superconductivity and charge order with $d$-wave form factor. Deviations from particle-hole symmetry, however, rapidly lift this degeneracy, despite the fact that the SU(2) symmetry is preserved at low energies. As a result, we find a strong suppression of charge order caused by the competing, leading superconducting instability. Across the antiferromagnetic phase transition, we also observe a shift in the charge order wave-vector from diagonal to axial. We discuss the implications of our results to the universal phase diagram of antiferromagnetic quantum-critical metals and to the elucidation of the charge order experimentally observed in the cuprates.