论文标题
SM $ _ {2} $ nimno $ _ {6} $ double perovskite中的磁性的微观见解
Microscopic insights of magnetism in Sm$ _{2} $NiMnO$ _{6} $ double perovskite
论文作者
论文摘要
由于不可避免地存在抗位点疾病（ASDS），具有独特的铁磁绝缘剂基态的双重钙壶的功能特性引起了争议。在这里，我们旨在研究SM $ _ {2} $ NIMNO $ _ {6} $（SNMO）双perovskite系统的本地和全局尺度上的磁性订购的起源。利用不同的校准途径在SNMO中生成不同的阳离子排列，并使用高能量（E $ \ sim $ 0.3 ev）检查相应的磁性配置，“热中子”，这有助于克服SM吸收以及记录总（Bragg's+diffuse）具有高动量的散射配置文件（Q $ _ Max $ _ Max $ _ Max} $ _amax} $ {Max} $ {Max} $ {Q $ _amax prom} c} $）。我们已经观察到，Ni-Mn Sublatice采用了远距离的共线铁磁$ f_ {x} f_ {z {z} $结构，具有相应的$ k $ =（0，0，0，0）的传播向量，低于订购温度T $ \ lyssim $ 160 k，与可变的ASD浓度无关。此外，在Ni-MN网络相对于NI-MN网络的SM传感矩的反平行极化的签名在t $ \ sellowsim $ 35 k的附近都注意到。真实的太空对分布功能计算的计算已通过Ni/Mn/Mn-Mn/ni/ni linkage bloadenening提供了直接可视化ASD的ASD。在弥漫性磁散射曲线上采用反向蒙特卡洛方法，我们观察到负自旋旋转相关函数，这表明Ni-Ni抗磁性交换相互作用范围为第一个最近的邻居距离。这些结果证实，阳离子有序的宿主基质中的ASD存在导致在较大温度范围内竞争的铁磁 - 抗铁磁阶段，从而定量控制了SNMO系统的温度相关的大量磁性可观察到的SNMO系统。
The functional characteristics of double perovskites with unique ferromagnetic-insulator ground state have been controversial due to the unavoidable presence of anti-site disorders (ASDs). Here, we aim to investigate the origin of magnetic ordering on local and global scales in Sm$_{2}$NiMnO$_{6}$ (SNMO) double perovskite system. Different calcination routes are exploited to generate different cation arrangements in SNMO and the corresponding magnetic configurations are examined using the high energy (E $ \sim $0.3 eV) `hot neutrons', which has helped to overcome Sm absorption as well as to record total (Bragg's+diffuse) scattering profiles with high momentum transfer (Q$ _{max} \sim $24 angstrom$ ^{-1} $). We have observed that the Ni-Mn sublattice adopts long range collinear ferromagnetic $ F_{x}F_{z} $ structure with commensurate $k$=(0, 0, 0) propagation vector, below ordering temperature T $ \lesssim $ 160 K, irrespective of variable ASD concentrations. In addition, the signatures indicating the antiparallel polarization of Sm paramagnetic moments with respect to Ni-Mn network, are noticed in the vicinity of anomalous magnetic transitions at T $ \lesssim $ 35 K. The real space pair distribution function calculations have provided a direct visualization of ASDs by means of broadening in Ni/Mn-Mn/Ni linkage. Employing the Reverse Monte Carlo approach on diffuse magnetic scattering profiles, we have observed the negative spin-spin correlation function which suggests the Ni-Ni antiferromagnetic exchange interactions ranging up to first nearest neighbor distance. These results confirm that the existence of ASDs in cation ordered host matrix leads to competing ferromagnetic-antiferromagnetic phases in a broad temperature range, which quantitatively governs the temperature dependent bulk magnetic observables of SNMO system.
