Doped Valence Bond Solid and Superconductivity on the Shastry-Sutherland Lattice

TL;DR

This paper explores how doping affects the ground states of a Mott insulator on the Shastry-Sutherland lattice, revealing the emergence of novel superconducting states influenced by valence bond order, with implications for experiments.

Contribution

It provides a unified theoretical framework for understanding both the valence-bond solid and doped superconducting states on the Shastry-Sutherland lattice using the t-J-V model.

Findings

Superconducting states emerge upon doping.

Properties depend on underlying valence bond order.

Implications for future experimental investigations.

Abstract

Motivated by recent experiments on SrCu$_2$(BO$_3$)$_2$, we investigate the ground states of the doped Mott insulator on the Shastry-Sutherland lattice. To provide a unified theoretical framework for both the valence-bond solid state found in undoped SrCu$_2$(BO$_3$)$_2$ and the doped counterpart being pursued in on-going experiments, we analyze the t-J-$V$ model via the bond operator formulation. It is found that novel superconducting states emerge upon doping with their properties crucially depending on the underlying valence bond order. Implications to future experiments are discussed.