Pradhan Suman Kalyan, Dalal Biswajit, Saha Rafikul Ali, Datta Raktim, Majumdar Subham, De Subodh Kumar
School of Materials Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India.
School of Physical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India.
J Phys Condens Matter. 2021 Jun 25;33(33). doi: 10.1088/1361-648X/ac066a.
Iridium-based double perovskites having mixed 3-5-4magnetic sub-lattices are expected to exhibit exotic magnetic phenomenon. In this paper, we report a study of structural, magnetic and transport properties of the mixed 3-5-4double perovskite SmCoIrO(SMCO), which crystallizes in monoclinic structure with space group2/and the crystal symmetry remains same throughout the measured temperature down to 15 K. High resolution synchrotron x-ray diffraction reveals an isostructural phase transition around 104 K. Magnetization measurements on polycrystalline samples indicate that SMCO orders ferrimagnetically at= 104 K; while, a second transition is observed below 10 K due to the rare-earth (Sm) ordering. The ferrimagnetic transition is well-understood by Néel's two-sublattice model, which is primarily ascribed to antiferromagnetic coupling between Coand Irsub-lattices. Electronic transport measurement shows the insulting behaviour of SMCO, which follows Mott variable-range hopping conduction mechanism. However, dielectric measurements as a function of temperature rules out the presence of magneto dielectric coupling in this compound.
具有混合3-5-4磁性亚晶格的铱基双钙钛矿有望展现出奇异的磁现象。在本文中，我们报道了对混合3-5-4双钙钛矿SmCoIrO（SMCO）的结构、磁性和输运性质的研究，该化合物结晶为单斜结构，空间群为2/，并且在低至15 K的整个测量温度范围内晶体对称性保持不变。高分辨率同步加速器X射线衍射揭示了在104 K左右的同结构相变。对多晶样品的磁化测量表明，SMCO在 = 104 K时铁磁有序；同时，由于稀土（Sm）有序化，在10 K以下观察到第二次转变。铁磁转变可以通过奈尔双亚晶格模型很好地理解，该模型主要归因于Co和Ir亚晶格之间的反铁磁耦合。电子输运测量表明SMCO具有绝缘行为，遵循莫特变程跳跃传导机制。然而，作为温度函数的介电测量排除了该化合物中存在磁电耦合的可能性。
