Abstract Multiferroics have attracted research interest for decades due to their potential applications. Multiferroics are relatively scarce due to the mutual exclusivity between magnetic and ferroelectric properties. New room-temperature multiferroics are looking forward to be exploited. Room-temperature multiferroic properties have been observed in a new rare-earth iron garnet (REIG), Nd3Fe5O12 (NdIG). The dielectric properties of NdIG over a wide temperature range (300 K–650 K) at different frequencies (100 Hz–1 MHz) and in the temperature range from 70 K to 300 K at 100 Hz are investigated herein. The results show that this material has two dielectric relaxations in the temperature range from 290 K to 525 K and a dielectric anomaly around the magnetic ordering temperature (565 K). The first dielectric relaxation in the temperature range from 290 K to 500 K is attributed to the conduction with an activation energy of 0.75 eV. The other dielectric relaxation in an elevated temperature range has an activation energy of 0.87 eV, which originates from the inhomogeneous structure. Furthermore, the ferroelectric polarization of approximately 28 μC/m2 at 77 K is determined by the positive-up-negative-down method and induced by the effective magnetic field created by the iron sublattice magnetic ordering and electric-dipole moments of the neodymium ions.

中文翻译：

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Nd3Fe5O12的介电和铁电性能

摘要 几十年来，多铁性材料因其潜在的应用而引起了研究兴趣。由于磁性和铁电特性之间的相互排斥性，多铁性材料相对稀缺。期待开发新的室温多铁性材料。在新的稀土铁石榴石 (REIG) Nd3Fe5O12 (NdIG) 中观察到了室温多铁性。本文研究了 NdIG 在不同频率 (100 Hz-1 MHz) 和 70 K 至 300 K 的温度范围 (100 Hz) 下的宽温度范围 (300 K-650 K) 内的介电性能。结果表明，该材料在 290 K 至 525 K 的温度范围内具有两个介电弛豫，并在磁有序温度 (565 K) 附近具有介电异常。在 290 K 到 500 K 的温度范围内的第一次介电弛豫归因于激活能为 0.75 eV 的传导。高温范围内的其他介电弛豫具有 0.87 eV 的活化能，这源于不均匀结构。此外，77 K 下大约 28 μC/m2 的铁电极化由正-上-负-下方法确定，并由铁亚晶格磁序和钕离子的电偶极矩产生的有效磁场感应。