Universal curve and long-range ferromagnetic order in the intermetallic compound Mn0.92Sn0.08CoGe

作者：Si, Xiaodong; Zhou, Keyi^*; Zhang, Rui; Ma, Xinxiu; Zhang, ZhanXian; Liu, Yongsheng^*

来源：Materials Research Express, 2018, 5(8): 086507.

DOI：10.1088/2053-1591/aad266

• MnCoGe
• magnetocaloric effect
• Curie temperature
• magnetic refrigeration

In this work, the universal curve, critical behavior and magnetocaloric effect of the intermetallic compound Mn0.92Sn0.08CoGe around room temperature have been investigated. Magnetic data indicate that Mn0.92Sn0.08CoGe exhibits the characteristic of second-order transition around the room temperature 286 K. Moreover, the universal curve, well fitted by a Lorentz function, further proves second-order nature of the transition. The critical exponents obtained from various techniques such as modified Arrott plot (MAP), Kouvel-Fisher (KF) method, and critical isotherm analysis (M(T-c)) are found to basically fulfill the Widom scaling relation: delta = 1 + gamma/beta and obey the scaling equation of M (H, epsilon) = epsilon(beta)f(+/-)(H /epsilon(beta+gamma)), revealing the extracted critical exponents are reliable. The obtained critical exponents are close to the prediction of the mean-field model, suggesting the existence of long-range magnetic interactions coupling with the exchange distance decaying as J(r) approximate to r(-4.4).

• 出版日期2018-8
• 单位东南大学; 上海电力大学