论文标题
准二维蜂窝化合物Incu $ _ {2/3} $ v $ _ {1/3} $ o $ $ $ _3 $
Ground state and low-temperature magnetism of the quasi-two-dimensional honeycomb compound InCu$_{2/3}$V$_{1/3}$O$_3$
论文作者
论文摘要
我们报告了NQR中的$^{115} $，$^{51} $ v NMR和$ $ $ $ $ SR光谱研究Incu $ _ {2/3} $ _ {2/3} $ v $ _ {2/3} $ _ {1/3} $ $ $ $ $ $ $ $ _3 $的低温磁性特性，一个Quasi-two dimensiality（2d）与Cu $^{2+} $ ions相关的抗磁性耦合旋转的晶格$ s = 1/2 $。尽管实验和理论上的努力很大，但最终尚未确定该材料的基态。特别是，有争议地讨论了两个大约$ \ sim 40 $ k和$ \ sim 20 $ k的特征温度，这些温度在不同的磁性测量中表现为异常。对实验数据的组合分析辅以交换常数的理论计算，使我们能够识别以下39 k的“中间”'quasi-2d静态旋转状态。这种自旋状态的特征是交错的磁化强度，温度演化与2D XY模型的预测一致。我们观察到，该状态在15 K处逐渐转化为完全发达的3D抗磁性néel状态。我们将这种扩展的准2D静态状态归因于蜂窝平面的有效磁去耦，这是由于层间交换相互作用的强烈挫败，从而抑制了整个平面之间的远程自旋旋转相关性。有趣的是，我们发现了拓扑berezinsky-kosterlitz-在蜂蜜2D静态状态下的拓扑berezinsky-kosterlitz的迹象。
We report a combined $^{115}$In NQR, $^{51}$V NMR and $μ$SR spectroscopic study of the low-temperature magnetic properties of InCu$_{2/3}$V$_{1/3}$O$_3$, a quasi-two dimensional (2D) compound comprising in the spin sector a honeycomb lattice of antiferromagnetically coupled spins $S=1/2$ associated with Cu$^{2+}$ ions. Despite substantial experimental and theoretical efforts, the ground state of this material was has not been ultimately identified. In particular, two characteristic temperatures of about $\sim 40$ K and $\sim 20$ K manifesting themselves as anomalies in different magnetic measurements are discussed controversially. A combined analysis of the experimental data complemented with theoretical calculations of exchange constants enabled us to identify below 39 K an ``intermediate'' quasi-2D static spin state. This spin state is characterized by a staggered magnetization with a temperature evolution that agrees with the predictions for the 2D XY model. We observe that this state gradually transforms at 15 K into a fully developed 3D antiferromagnetic Néel state. We ascribe such an extended quasi-2D static regime to an effective magnetic decoupling of the honeycomb planes due to a strong frustration of the interlayer exchange interactions which inhibits long-range spin-spin correlations across the planes. Interestingly, we find indications of the topological Berezinsky-Kosterlitz-Thouless transition in the quasi-2D static state of the honeycomb spin-1/2 planes of InCu$_{2/3}$V$_{1/3}$O$_3$.
