本研究以固相合成法製備(Y0.6Sm0.6Eu0.6Dy0.6Er0.6)Fe5O12 (Y=0.6)，並以1200 ℃、1250 ℃和1300 ℃持溫24小時燒結，透過X光繞射(XRD)分析確認三個燒結溫度皆能合成出純相高熵固溶體石榴石材料。Williamson-Hall分析指出，Crystallite size隨燒結溫度增加而增大，因此可以觀察到1300 ℃燒結的樣品具有最大的平均粒徑和最緻密的微觀結構。後續進一步以此高熵石榴石成分為基礎，將釔含量減少平均分配於其餘四個稀土離子，分別為(Y0.4Sm0.65Eu0.65Dy0.65Er0.65)Fe5O12 (Y=0.4)、(Y0.2Sm0.7Eu0.7Dy0.7Er0.7)Fe5O12 (Y=0.2)和(Sm0.75Eu0.75Dy0.75Er0.75)Fe5O12 (Y=0)。XRD分析顯示隨著釔含量降低，主峰(420)向低角度偏移，結合TOPAS分析證實離子半徑較大的稀土濃度增加會促使晶格體積膨脹。同時SEM分析也指出組態熵值的提升能顯著抑制晶粒成長。
在磁性方面，中、高熵系列石榴石樣品矯頑力相較於傳統石榴石材料大幅降低至17.30 Oe至20.01 Oe，主要歸因於隨機取向的磁晶各向異性抵銷，有助於減少磁滯損耗，展現高熵材料典型的雞尾酒效應。截取1000 Oe至15000 Oe磁化曲線以趨近飽和律(LAS)擬合分析，結果顯示有效各向異性常數隨著材料組態熵值提升由23036 erg/cm3顯著上升至28060 erg/cm3，表明晶格扭曲效應隨著熵值的提升，引發更大的應力各向異性。晶格的應變產生許多釘紮點，在磁導率的量測中限制磁疇壁的移動，推升磁導率實部響應至50 MHz，強烈的有效各向異性也擴展旋磁自旋共振頻率至1 GHz。
高熵效應的混亂度使高熵石榴石材料在低溫下轉變為團簇自旋玻璃態，其凍結溫度Tf與外加磁場的關係可以由de Almeida-Thouless (AT) line擬合，得出平均場值n=0.68、自旋玻璃溫度T_f (0)約為344 K。顯示晶格扭曲效應產生的有效各向異性將原先符合Heisenberg模型的3維翻轉行為的磁矩束縛於局域的易磁化軸上，使磁矩行為降維成1維Ising自旋行為，轉變為極大不可逆性的Ising-like自旋玻璃行為。此種效應也讓高熵石榴石材料在100 Oe的磁場下凍結溫度達到299 K。

In this study, medium- and high-entropy garnet materials, such as (Y0.6Sm0.6Eu0.6Dy0.6Er0.6)Fe5O12, were prepared via a solid-state synthesis method. XRD analysis proves the successful synthesis of pure-phase garnet materials. Furthermore, analysis of the XRD patterns using the Williamson-Hall method confirms the presence of significant lattice strain in both medium- and high-entropy garnets. Compare to single rare earth garnet, the coercivity was significantly reduced to between 17.30 Oe and 20.01 Oe, which helps lower hysteresis loss. The magnetization curves from 1000 Oe to 15,000 Oe were extracted and fitted using the Law of Approach to Saturation (LAS). The results of which showed that the effective anisotropy constant significantly increased from 23,036 erg/cm³ to 28,060 erg/cm³. This strong effective anisotropy also extended the spin resonance frequency to 1 GHz. The lattice strain generated numerous pinning sites that restricted the movement of domain walls during permeability measurements, pushing the real part response of the permeability up to 50 MHz. The high degree of disorder from the high-entropy effect caused the high-entropy garnet materials to transition into a spin-glass state at low temperatures. The relationship between the freezing temperature (T_f) and the applied magnetic field can be fitted by the de Almeida-Thouless line, yielding a mean-field value of n=0.68, causing the magnetic moment behavior to conform to 1-dimensional Ising-like spin-glass behavior. This effect also enabled the high-entropy garnet materials to achieve a freezing temperature of 299 K under a 100 Oe magnetic field.

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