Supersolid phases of a doped valence-bond quantum antiferromagnet: Evidence for a coexisting superconducting order parameter

TL;DR

This paper presents evidence that doping a valence-bond quantum antiferromagnet leads to novel supersolid phases where superconductivity coexists with valence-bond order, supported by theoretical and numerical analysis.

Contribution

It introduces a theoretical framework showing the emergence of supersolid phases in doped valence-bond antiferromagnets, combining fermionic mean-field theory and exact diagonalization.

Findings

Identification of supersolid phases with coexisting superconductivity and valence-bond order

Strong theoretical support for the stability of these phases

Potential relevance to high-$T_c$ cuprates and frustrated superconductors

Abstract

Motivated by numerical evidence of the valence bond groundstate of the two-dimensional Heisenberg pyrochlore lattice, we argue using a $t$-$J$ model that it evolves under doping into novel phases characterized by superconductivity coexisting with the underlying valence-bond solid order. A fermionic mean-field theory supplemented by exact diagonalization results provide strong arguments in favor of the stability of such supersolid phases. The resemblance with modulated superconducting patterns in high-$T_c$ cuprates as well as possible relevance to frustrated noncuprate superconductors such as spinels and pyrochlores is discussed.