We report a comprehensive muon spectroscopy study of the Zn-barlowite series of \(S=\frac{1}{2}\) kagomé antiferromagnets, Zn_xCu_4−x(OH)₆FBr, for x = 0.00 to 0.99(1). By combining muon spin relaxation and rotation measurements with state-of-the-art density-functional theory muon-site calculations, we observe the formation of both μ–F and μ–OH complexes in Zn-barlowite. From these stopping sites, implanted muon spins reveal the suppression of long-range magnetic order into a possible quantum spin liquid state upon the increasing concentration of Zn-substitution. In the parent compound (x = 0), static long-range magnetic order below T_N = 15 K manifests itself in the form of spontaneous oscillations in the time-dependent muon asymmetry signal consistent with the dipolar fields expected from the calculated muon stopping sites and the previously determined magnetic structure of barlowite. Meanwhile, in the x = 1.0 end-member of the series—in which antiferromagnetic kagomé layers of Cu²⁺\(S=\frac{1}{2}\) moments are decoupled by diamagnetic Zn²⁺ ions—we observe that dynamic magnetic moment fluctuations persist down to at least 50 mK, indicative of a quantum disordered ground state. We demonstrate that this crossover from a static to dynamic magnetic ground state occurs for compositions of Zn-barlowite with x > 0.5, which bears resemblance to the dynamical behaviour of the widely studied Zn-paratacamite series that contains the quantum spin liquid candidate herbertsmithite.

我们报告了\（S = \ frac {1} {2} \） kagomé反铁磁体Zn _x Cu _{4− x}（OH）₆ FBr的Zn-重晶石系列的全面muon光谱研究，x  = 0.00至0.99（ 1）。由μ介子自旋松弛和旋转测量与国家的最先进的密度泛函理论μ介子现场计算相结合，我们观察二者的形成μ -F和μ -OH络合物的Zn-barlowite。从这些停止位点开始，注入的介子自旋揭示了随着Zn取代浓度的增加，远距离磁阶被抑制为可能的量子自旋液态。在母体化合物（x = 0）时，低于T _N  = 15 K的静态远程磁阶以与时间相关的μon不对称信号中的自发振荡的形式表现出来，该信号与从计算出的muon停止位点和先前确定的磁结构所预期的偶极场一致的重晶石。同时，在该 序列的x = 1.0端部成员中，Cu ^2+的反铁磁kagomé层（S = \ frac {1} {2} \）矩被反磁性Zn ²⁺解耦离子—我们观察到，动态磁矩波动至少会降低到50 mK，这表明量子无序基态。我们证明，这种从静态到动态磁基态的转换发生在x  > 0.5的锌-巴洛石的成分上，这与广泛研究的包含量子自旋液体候选铁矾的Zn-paracamelite系列的动力学行为相似。