We report the magnetic susceptibility, specific heat, and muon spin relaxation results of the $5d^1$ double perovskite ${\mathrm{Ba}}_2{\mathrm{YWO}}_6$. The dc magnetic susceptibility shows two distinct Curie-Weiss regimes and a sub-Curie-Weiss increase $T^{-n}$ with $n=0.75\left(1\right)$ for $T=3\text{–}100$ K, alluding to the presence of random magnetism. The ac magnetic susceptibility reveals a spin freezing at $T_f\sim 0.3$ K with the activation energy of $\mathrm{\Delta }/k_B=27.6$ K. The specific heat data exhibit the pseudogap behavior at 25 K and the subsequent power-law dependence with decreasing temperature, indicating the gradual spin freezing with the quenching of orbital fluctuations. However, the muon spin relaxation data display only a weak muon spin depolarization with lacking long-range magnetic ordering down to 26 mK. Taken together, our results suggest that ${\mathrm{Ba}}_2{\mathrm{YWO}}_6$ is the proximate realization of a random spin-orbit dimer state.

中文翻译：

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5d1双钙钛矿Ba2YWO6中价键玻璃的实验证据

我们报告了磁化率、比热和μ子自旋弛豫结果 $5d^1$ 双钙钛矿 ${巴}_2{\mathrm{永沃}}_6$. 直流磁化率显示出两种不同的居里-魏斯状态和亚居里-魏斯增加${吨}^{-n}$ 和 $n=0.75\left(1\right)$ 为了 $吨=3\text{——}100$ K，暗指随机磁性的存在。交流磁化率显示自旋冻结在${吨}_F～0.3$ K 的活化能为 $\mathrm{\Delta }/{克}_{乙}=27.6$ K. 比热数据在 25 K 时表现出赝隙行为，随后随着温度的降低呈现幂律依赖性，表明随着轨道波动的淬灭，自旋逐渐冻结。然而，μ子自旋弛豫数据仅显示微弱的μ子自旋去极化，缺乏低至26 mK的长程磁序。综上所述，我们的结果表明${巴}_2{\mathrm{永沃}}_6$ 是随机自旋轨道二聚体状态的近似实现。