Muon spin relaxation study on the Shastry−Sutherland lattice antiferromagnet Pr2Ga2BeO7

In the study of frustrated magnetism, the Shastry−Sutherland lattice (SSL), an arrangement of orthogonal dimers with antiferromagnetic interdimer coupling J2 and the intradimer coupling J1, represents one of the few exactly solvable structures. The SSL ground state is known when the ratio J2/J1 is small or large, but the states of the intermediate values are still unclear. Rare-earth-based SSL frustrated magnets can give rise to diverse exotic magnetic ground states such as quantum spin liquid. We have recently synthesized single crystals of a new family of rare-earth based SSL compound Pr2Ga2BeO7 and characterized it using magnetization, heat capacity and thermal conductivity experiments, which indicate that Pr2Ga2BeO7 is an ideal candidate of quantum spin liquids. In order to analyze the magnetic fluctuations from the spin dynamiscs to accomplish the manuscript and give direction for the inelastic neutron scattering at JAEA on Feb. 2024, we intend to measure the muon spin rotation and relaxation.

在阻挫磁学（frustrated magnetism）研究领域，沙斯特里-萨瑟兰晶格（Shastry−Sutherland lattice, SSL）由正交二聚体构成，兼具二聚体内耦合J₁与二聚体间反铁磁耦合J₂，是少数可严格求解的磁学结构之一。当J₂/J₁比值处于极小或极大区间时，SSL的基态已被探明，但该比值取中间值时的磁态仍未明确。稀土基阻挫SSL磁体可展现出多样的新奇磁基态，例如量子自旋液体（quantum spin liquid）。我们近期合成了新型稀土基SSL化合物Pr₂Ga₂BeO₇的单晶，并通过磁化强度、热容与热导率实验完成表征，结果表明Pr₂Ga₂BeO₇是量子自旋液体的理想候选体系。为分析自旋动力学相关的磁涨落以完成论文撰写，并为2024年2月于JAEA开展的非弹性中子散射实验提供指导，我们计划开展μ子自旋旋转与弛豫（muon spin rotation and relaxation）测量。