Song Jiyue, Zhao Bangchuan, Yin Lihua, Qin Yanfeng, Zhou Jiafeng, Wang Dong, Song Wenhai, Sun Yuping
Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, People's Republic of China.
Dalton Trans. 2017 Sep 12;46(35):11691-11697. doi: 10.1039/c7dt02254a.
The structural, magnetic, electrical and dielectric properties of an Ir-based double perovskite compound, LaCoIrO, have been investigated. The sample undergoes a paramagnetic-ferromagnetic transition at T, followed by a reentrant spin-glass transition at lower temperatures. The reentrant spin glass state in LaCoIrO is associated with the competitions of the antiferromagnetic coupling between Ir and Co ions and the ferromagnetic clusters. LaCoIrO shows a semiconducting transport behavior in the temperature range 65 to 360 K and the transport behavior can be well described by the three-dimensional Mott variable range hopping conduction mechanism. Moreover, a strong frequency dependence of dielectric constant behavior for LaCoIrO is observed and the dielectric relaxation can be ascribed to the electron hopping between different transition metal ions. In addition, the isothermal magnetic field dependent dielectric constant measurements show that a clear magnetodielectric coupling effect exists in LaCoIrO at low temperatures.
对一种基于铱的双钙钛矿化合物LaCoIrO的结构、磁性、电学和介电性质进行了研究。该样品在温度T处经历顺磁-铁磁转变，随后在较低温度下发生重入自旋玻璃转变。LaCoIrO中的重入自旋玻璃态与铱离子和钴离子之间的反铁磁耦合以及铁磁团簇的竞争有关。LaCoIrO在65至360 K的温度范围内表现出半导体输运行为，并且该输运行为可以通过三维莫特变程跳跃传导机制得到很好的描述。此外，观察到LaCoIrO的介电常数行为具有很强的频率依赖性，并且介电弛豫可归因于不同过渡金属离子之间的电子跳跃。另外，等温磁场依赖介电常数测量表明，LaCoIrO在低温下存在明显的磁电耦合效应。
