The Tb1−xYxMn2Ge2 series (x = 0, 0.1, 0.2) compounds are found to exhibit two magnetic phase transitions with decreasing temperature: from the paramagnetic state to the antiferromagnetic interlayer state at TNinter and from an antiferromagnetic interlayer structure to a collinear ferrimagnetic interlayer structure at TCinter. Compared with the slight change of TNinter (409 K, 410 K and 417 K for x = 0, 0.1 and 0.2 respectively), the replacement of Y for Tb leads to a significant decrease in TCinter from 97.5 K for x = 0 to 74.6 K for x = 0.2. The variation in TCinter can be ascribed to the combination of two effects: (1) chemical pressure and (2) magnetic dilution effect by Y substitution for Tb. Besides, a strong anisotropic magnet-volume effect has been detected around TCinter in all compounds with Δa/a = 0.125%, 0.124% and 0.130% for x = 0, 0.1 and 0.2, respectively while no obvious effect is detected along the c-axis. The maximum magnetic entropy change were found to be −ΔSmax = 9.1 J kg−1 K−1, 11.9 J kg−1 K−1 and 6.3 J kg−1 K−1 with a field change from 0 T to 5 T for x = 0, 0.1, 0.2 respectively.
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机译：发现Tb1-xYxMn2Ge2系列（x = 0，0.1，0.2）化合物在降低的温度下表现出两个磁相变：从顺磁态到TN inter 的反铁磁层间态和从反铁磁TC inter 的共层亚铁层间结构。与TN inter 的细微变化（x = 0，分别为0.1和0.2分别为409 K，410 K和417 K）相比，用Y代替Tb导致TC inter 从x = 0的97.5 K到x = 0.2的74.6K。 TC inter 的变化可归因于两种效应的组合：（1）化学压力和（2）通过Y替代Tb的磁稀释效应。此外，在Δa/ a = 0.125％，x = 0、0.1和0.2分别为Δa/ a = 0.125％，0.124％和0.130％的所有化合物中，在TC inter 附近均检测到强各向异性磁体积效应。沿c轴检测到明显的效果。发现最大磁熵变为-ΔSmax= 9.1 J kg -1 K -1 ，11.9 J kg -1 K −1 和6.3 J kg −1 K -1 ，其中x = 0、0.1、0.2的场分别从0 T变为5T。
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