Deconfined Gapless phases and criticalities in Shastry-Sutherland Antiferromagnet
Abstract
Antiferromagnets on the Shastry-Sutherland lattice have attracted lots of research interest due to the possible existence of deconfined criticality. In the present work, we study the -- model using Variational Monte Carlo (VMC) method, where , , stand for the nearest-neighbor, next nearest neighbor and ring exchange interactions respectively. An empty plaquette (EP) phase with spontaneous mirror symmetry breaking is reproduced. However, the EP phase in the VMC approach is deconfined and have Majorana-type gapless spinon excitations, which is qualitatively different from the EP phase in literature. The central observation of the present study is the gapless Quantum spin liquid phase resulting from the competition between the EP phase, the full plaquette (FP) phase and the antiferromagnetic N\'eel phase. While the phase transition from the QSL phase to the EP phase is likely of Landau-Ginzburg type, the continuous transitions to the confined FP and N\'eel phases are exotic and need to be further explored.
Keywords
Cite
@article{arxiv.2503.20122,
title = {Deconfined Gapless phases and criticalities in Shastry-Sutherland Antiferromagnet},
author = {Lvcheng Chen and Zheng-Xin Liu},
journal= {arXiv preprint arXiv:2503.20122},
year = {2026}
}