Abstract In the present study, the impact of holmium (Ho) substitution on structural, spectral, dielectric and magnetic behavior of Li1.2Zn0.4HoxFe2−xO4 (0.00 ≤ x ≤ 0.15) ferrites was investigated. The development of spinel phase and structural changes induced by Ho doping were confirmed by X-ray diffraction. The accommodation of Ho ions into spinel lattice was restricted for x ≥ 0.06 as indicated by ortho phase (HoFeO3) traces. The decrease in lattice parameter (a) was attributed to the segregation of Ho ions on grain boundaries. FTIR spectra featured two intrinsic vibrational bands v1 (617 cm−1) and v2 (488 cm−1) for x = 0 due to tetrahedral and octahedral vibrations respectively. The compositional dependence of force constants and bond lengths has explained on the basis of cations distribution and oxygen-cation bond distances of respective sites. The addition of Ho ions decreased the saturation magnetization and optimized the coercivity from 59 to 335 Oe, proposing these ferrites for magnetic recording media. Dielectric results for the entire range of frequency (1 MHz to 3 GHz) revealed that ac conductivity increased from 3.5 × 105 to 1.8 × 106 (Ω-cm)−1 up to x = 0.09 and then it decreased slightly for x = 0.12. The effective contribution of grain-interior mechanism to dielectric behavior was confirmed by complex impedance study. The results of dielectric studies displayed that Ho doped lithium ferrites are suitable low loss potential materials for high frequency based applications.

中文翻译：

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通过 Ho 掺杂调节 Li-Zn 铁氧体的磁性和高频介电行为

摘要 在本研究中，研究了钬 (Ho) 取代对 Li1.2Zn0.4HoxFe2-xO4 (0.00 ≤ x ≤ 0.15) 铁氧体的结构、光谱、介电和磁行为的影响。X 射线衍射证实了由 Ho 掺杂引起的尖晶石相的发展和结构变化。如邻相 (HoFeO3) 迹线所示，将 Ho 离子容纳到尖晶石晶格中时 x ≥ 0.06 受到限制。晶格参数 (a) 的降低归因于 Ho 离子在晶界上的偏析。由于四面体和八面体振动，FTIR 光谱在 x = 0 时具有两个固有振动带 v1 (617 cm-1) 和 v2 (488 cm-1)。力常数和键长的组成依赖性已经根据各个位点的阳离子分布和氧-阳离子键距进行了解释。Ho 离子的加入降低了饱和磁化强度，并将矫顽力从 59 Oe 优化到 335 Oe，建议将这些铁氧体用于磁记录介质。整个频率范围（1 MHz 至 3 GHz）的介电结果表明，交流电导率从 3.5 × 105 增加到 1.8 × 106 (Ω-cm)-1 至 x = 0.09，然后在 x = 0.12 时略微下降。复阻抗研究证实了晶粒内部机制对介电行为的有效贡献。介电研究结果表明，Ho 掺杂的锂铁氧体是适用于高频应用的低损耗潜在材料。Ho 离子的加入降低了饱和磁化强度，并将矫顽力从 59 Oe 优化到 335 Oe，建议将这些铁氧体用于磁记录介质。整个频率范围（1 MHz 至 3 GHz）的介电结果表明，交流电导率从 3.5 × 105 增加到 1.8 × 106 (Ω-cm)-1 至 x = 0.09，然后在 x = 0.12 时略微下降。复阻抗研究证实了晶粒内部机制对介电行为的有效贡献。介电研究结果表明，Ho 掺杂的锂铁氧体是适用于高频应用的低损耗潜在材料。Ho 离子的加入降低了饱和磁化强度，并将矫顽力从 59 Oe 优化到 335 Oe，建议将这些铁氧体用于磁记录介质。整个频率范围（1 MHz 至 3 GHz）的介电结果表明，交流电导率从 3.5 × 105 增加到 1.8 × 106 (Ω-cm)-1 至 x = 0.09，然后在 x = 0.12 时略微下降。复阻抗研究证实了晶粒内部机制对介电行为的有效贡献。介电研究结果表明，Ho 掺杂的锂铁氧体是适用于高频应用的低损耗潜在材料。整个频率范围（1 MHz 至 3 GHz）的介电结果表明，交流电导率从 3.5 × 105 增加到 1.8 × 106 (Ω-cm)-1 至 x = 0.09，然后在 x = 0.12 时略微下降。复阻抗研究证实了晶粒内部机制对介电行为的有效贡献。介电研究结果表明，Ho 掺杂的锂铁氧体是适用于高频应用的低损耗潜在材料。整个频率范围（1 MHz 至 3 GHz）的介电结果表明，交流电导率从 3.5 × 105 增加到 1.8 × 106 (Ω-cm)-1 至 x = 0.09，然后在 x = 0.12 时略微下降。复阻抗研究证实了晶粒内部机制对介电行为的有效贡献。介电研究结果表明，Ho 掺杂的锂铁氧体是适用于高频应用的低损耗潜在材料。