Abstract Multiple rare earth metal cations (Gd, Yb, Ho and Pr) were doped in yttrium iron garnet (YIG) nanocrystalline ferrites. Following five samples i.e. YIG (Y 3 Fe 5 O 12 ), Gd doped YIG (Y 2.8 Gd 0.2 Fe 5 O 12 ), Pr doped YIG (Y 2.8 Pr 0.2 Fe 5 O 12 ), Ho doped YIG (Y 2.8 Ho 0.2 Fe 5 O 12 ) and Yb doped YIG (Y 2.8 Yb 0.2 Fe 5 O 12 ) were prepared using sol-gel auto-combustion synthesis route. The samples were characterized via XRD, FTIR, SEM and VSM whereas VNA was also used to evaluate these samples for high frequency applications. XRD analysis confirms the peaks of garnet ferrites which show cubic phase structure for all YIG doped samples. The lattice constant in all the substituted garnet nanoferrites initially increased and then consequently decreased as the doping increased except for Pr-substituted YIG nanoferrites. This is due to the greater ionic radii of Pr as compared to other doped YIG nanoferrites. FTIR was used to find out the garnet phase in all the substituted YIG nanoferrites. The morphological features of the garnet nanoferrites were observed using the SEM images. High frequency measurements such as permittivity, permeability, dielectric losses, ac conductivity, electric modulus and Q factor of YIG and doped YIG nanoferrites were measured using VNA. Saturation magnetization, remanence, coercivity, squareness ratio, Bohr magneton and magneto crystalline anisotropy were measured from the magnetic hysteresis loops recorded by VSM. Pr-doped YIG show better dielectric and magnetic properties with lower losses at higher frequency suggest the use of these garnet nanoferrites for microwave high frequency devices and applications.

中文翻译：

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用于高频应用的 YIG 稀土掺杂（Gd、Pr、Ho、Yb）纳米铁氧体的结构和电磁评估

摘要 在钇铁石榴石（YIG）纳米晶铁氧体中掺杂了多种稀土金属阳离子（Gd、Yb、Ho和Pr）。以下五个样品，即YIG (Y 3 Fe 5 O 12 )、Gd掺杂YIG (Y 2.8 Gd 0.2 Fe 5 O 12 )、Pr掺杂YIG (Y 2.8 Pr 0.2 Fe 5 O 12 )、Ho掺杂YIG (Y 2.8 Ho 0.2 ) Fe 5 O 12 )和Yb掺杂YIG(Y 2.8 Yb 0.2 Fe 5 O 12 )采用溶胶-凝胶自燃合成路线制备。样品通过 XRD、FTIR、SEM 和 VSM 进行表征，而 VNA 也用于评估这些样品的高频应用。XRD 分析证实了石榴石铁氧体的峰，所有 YIG 掺杂的样品均显示立方相结构。除了 Pr 取代的 YIG 纳米铁氧体之外，所有取代的石榴石纳米铁氧体的晶格常数最初都增加，然后随着掺杂的增加而降低。这是由于与其他掺杂的 YIG 纳米铁氧体相比，Pr 的离子半径更大。FTIR 用于找出所有取代的 YIG 纳米铁氧体中的石榴石相。使用 SEM 图像观察石榴石纳米铁氧体的形态特征。使用 VNA 测量 YIG 和掺杂 YIG 纳米铁氧体的高频测量值，例如介电常数、磁导率、介电损耗、交流电导率、电模量和 Q 因子。从 VSM 记录的磁滞回线测量饱和磁化强度、剩磁、矫顽力、矩形比、玻尔磁子和磁晶各向异性。Pr 掺杂的 YIG 显示出更好的介电和磁性能，并且在更高的频率下损耗更低，这表明这些石榴石纳米铁氧体可用于微波高频设备和应用。