This study emphasises on synthesis of ferrite nano powders via hydrothermal route within the compositional range of NiZnCoFe O (x = 0.00 to 0.05 in steps of 0.01 wt%). Structural analysis via XRD and FTIR unveiled the cubic spinal structure, confirmed by signature absorption bands existence in the infrared spectra. The FESEM analysis revealed the morphological characteristics of ferrite crystals, while characterizations indicated a diminution in crystallite sizes from 53 to 37 nm. The magnetic behaviour displayed the existed correlation between Ms and Y–K angles along with finite size effects of the samples. Notably, low coercively values (0.13 Oe to 1.09 Oe) and magneto crystalline anisotropy pointed towards the magnetic quality of the ferrites with soft nature. Exhibited dielectric loss factor near 10, and ac-conductivity (σ) within the range of 10S/m to 10S/m of the samples indicates their improved dielectric properties. Further analysis from UV–vis. Diffuse reflectance (UV-DRS), PL spectroscopy, and Raman studies exhibits slight variations in optical band gaps, and vibrational modes due to varying cobalt doping concentrations. The evaluation of optical limiting characteristics using the Z-scan technique revealed absorption coefficients ranging from 1.40 to 4.80 × (10 m/W) and onset limiting values between 1.93 W/m and 1.11 W/m. These findings position the Ni–Zn–Co ferrites as promising contenders for optical limiting applications owing to their optical nonlinearity and absorption characteristics.

中文翻译：

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探索钴掺杂镍锌纳米材料的非线性光学吸收

本研究重点是在 NiZnCoFe O 的组成范围内通过水热法合成铁氧体纳米粉末（x = 0.00 至 0.05，步长为 0.01 wt%）。通过 XRD 和 FTIR 进行的结构分析揭示了立方脊柱结构，并通过红外光谱中存在的特征吸收带证实了这一点。 FESEM 分析揭示了铁氧体晶体的形态特征，而表征表明微晶尺寸从 53 nm 减小到 37 nm。磁性行为显示了 Ms 和 Y-K 角之间存在的相关性以及样品的有限尺寸效应。值得注意的是，低矫顽力值（0.13 Oe 至 1.09 Oe）和磁晶各向异性表明铁氧体的磁性质量具有柔软性。样品的介电损耗因数接近10，交流电导率(σ)在10S/m至10S/m范围内，表明其介电性能得到改善。通过紫外可见分光光度法进行进一步分析。漫反射 (UV-DRS)、PL 光谱和拉曼研究显示，由于钴掺杂浓度不同，光学带隙和振动模式略有变化。使用 Z 扫描技术对光限幅特性的评估显示，吸收系数范围为 1.40 至 4.80 × (10 m/W)，起始限值范围为 1.93 W/m 至 1.11 W/m。这些发现使 Ni-Zn-Co 铁氧体由于其光学非线性和吸收特性而成为光学限幅应用的有希望的竞争者。