Magnetic frustration control through tunable stereochemically driven disorder in entropy-stabilized oxides
Magnetic frustration control through tunable stereochemically driven disorder in entropy-stabilized oxides
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DOI：
10.1103/physrevmaterials.3.104420
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发表时间：
2019-10-28
影响因子：
3.4
通讯作者：
Heron, John T.
中科院分区：
文献类型：
--
作者：
Meisenheimer, Peter B.;Williams, Logan D.;Heron, John T.
熵稳定的氧化物具有大的构型熵，其允许包括不同构型中的典型不混溶浓度的物质的独特能力。特别是在氧化物中，其中物理行为与立体化学和电子结构密切相关，熵稳定化创建了一个独特的平台，以定制极端结构和化学无序的相互作用，以实现前所未有的功能。在这里，我们控制立体化学驱动的结构紊乱单晶，岩盐，（MgCoNiCuZn）O-型熵稳定的氧化物通过掺入铜2+阳离子。我们利用无序来调整反铁磁结构中的玻璃化程度。由Jahn-Teller效应驱动的结构扭曲导致Co阳离子位点上的价态差异，其延伸到磁晶格的稀释和无序。自旋玻璃模型表明，分数自旋有序的磁晶格可以调整约65%。这些发现表明熵稳定作为一种工具，用于控制功能现象。
Entropy-stabilized oxides possess a large configurational entropy that allows for the unique ability to include typically immiscible concentrations of species in different configurations. Particularly in oxides, where the physical behavior is strongly correlated to stereochemistry and electronic structure, entropic stabilization creates a unique platform to tailor the interplay of extreme structural and chemical disorder to realize unprecedented functionalities. Here, we control stereochemically driven structural disorder in single crystalline, rocksalt, (MgCoNiCuZn)O-type entropy-stabilized oxides through the incorporation of Cu2+ cations. We harness the disorder to tune the degree of glassiness in the antiferromagnetic structure. Structural distortions driven by the Jahn-Teller effect lead to a difference in valence on the Co cation sites, which extends to dilution and disorder of the magnetic lattice. A spin glass model reveals that the fractional spin ordering of the magnetic lattice can be tuned by similar to 65%. These findings demonstrate entropy-stabilization as a tool for control of functional phenomena.