发表机构
Department of Materials Science and Engineering, Virginia Tech; Department of Mechanical Engineering, Virginia Tech（弗吉尼亚理工大学材料科学与工程系; 弗吉尼亚理工大学机械工程系）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文用SEAQT模型统一比较三种尖晶石软磁铁氧体的动态磁响应，发现Mn-Zn铁氧体在磁化变化和高频性能上最优，但各材料在不同指标上各有优势，该模型可作为铁氧体筛选工具而非损耗预测器。
AI 中文摘要
为交变场应用选择软磁铁氧体需要权衡磁响应、耗散、非线性和发热。我们采用场驱动的陡峭熵升量子热力学（SEAQT）模型，在统一的第一性原理框架内比较Fe$_3$O$_4$、MnFe$_2$O$_4$和(Mn$_{0.5}$Zn$_{0.5}$)Fe$_2$O$_4$的电子、声子和磁振子响应。该模型处理空间均匀的纵向弛豫，忽略畴壁运动、横向转动、共振、涡流效应和热移除。我们对三种材料均使用$\tau_e=0.05$ ps和$\tau_p=3$ ps，有效纵向磁振子弛豫时间分别为500、200和85 ps；这些基于文献的数值是模型输入，而非对实测损耗的拟合。在此框架内，Mn-Zn铁氧体产生最大的峰值纵向磁化变化，在高频下保持其响应最佳，并显示最大的每周期功和峰峰磁振子温度变化，而MnFe$_2$O$_4$产生最大的归一化$\chi''$峰。因此，没有单一铁氧体在所有指标上均排名最高：优选材料取决于所关注的性能、频率、场振幅和阳离子构型。因此，该模型提供了用于铁氧体工程比较的谱分辨和动力学分辨筛选工具，而非总磁芯损耗的预测。
英文摘要
Selecting soft ferrites for alternating-field applications requires balancing magnetic response, dissipation, nonlinearity, and heating. We use a field-driven steepest-entropy-ascent quantum thermodynamic (SEAQT) model to compare the electron, phonon, and magnon responses of Fe$_3$O$_4$, MnFe$2$O$4$, and (Mn${0.5}$Zn${0.5}$)Fe$_2$O$_4$ within a common first-principles framework. The model treats spatially uniform longitudinal relaxation and neglects domain-wall motion, transverse rotation, resonance, eddy-current effects, and heat removal. We use $τ_e=0.05$ ps and $τ_p=3$ ps for all three materials, with effective longitudinal magnon relaxation times of 500, 200, and 85 ps, respectively; these literature-motivated values are model inputs, not fits to measured losses. Within this framework, the Mn--Zn ferrite gives the largest peak longitudinal magnetization change, retains its response best at high frequency, and shows the largest work per cycle and peak-to-peak magnon temperature change, whereas MnFe$_2$O$_4$ gives the largest normalized $χ''$ peak. Thus, no single ferrite ranks highest across all metrics: the preferred material depends on the property, frequency, field amplitude, and cation configuration of interest. The model therefore provides a spectrum- and kinetics-resolved screening tool for engineering comparison of ferrites rather than a prediction of total core loss.
