论文标题
调整comn $ _ {0.88} $ cu $ _ {0.12} $ ge的磁结构相变
Tuning magnetostructural phase transition in CoMn$_{0.88}$Cu$_{0.12}$Ge by application of hydrostatic pressure
论文作者
论文摘要
COMN $ _ {0.88} $ CU $ _ {0.12} $ ge化合物的结构和磁性特性已使用X射线衍射（XRD）和差分扫描量热法（DSC）进行了研究，并伴随着对高达12 kbar的磁性压力进行研究的研究。已经发现，在低温下占主导地位的Tinisi型的矫正晶体结构变成了六角形Ni $ _2 $ _2 $ intype Onepe，略高于200 k。结构过渡是一阶类型的一阶类型，如存在于20 k的不同热分子的存在，以超过20 k的速度$。 238 K，然后在较低的温度下进行额外的异常 - 后者与结构过渡有关。静水压力的应用导致纯磁过渡的温度分离，其库里温度$ t_c $随着施加的压力慢慢增加，而磁结构过渡的特征是临界温度随着压力增加而迅速降低。比较研究化合物的DSC数据和同构化合物$ _ {0.95} $ cu $ _ {0.05} $ ge One使一个人可以确定熵变化的结构和磁成分是可能的。
Structural and magnetic properties of the CoMn$_{0.88}$Cu$_{0.12}$Ge compound have been investigated using X-ray diffraction (XRD) and differential scanning calorimetry (DSC) accompanied with investigation of magnetic properties under applied hydrostatic pressure up to 12 kbar. It has been found that the orthorhombic crystal structure of the TiNiSi-type, which is dominant at low temperatures, turns into the hexagonal Ni$_2$In-type one, slightly above 200 K. The structural transition is of the first-order type as confirmed by presence of distinct thermal hysteresis exceeding 20 K. The ac magnetic measurements indicate a ferromagnetic order below the Curie temperature $T_C$ of 238 K, followed by additional anomaly at lower temperatures - the latter one being related to the structural transition. Application of hydrostatic pressure leads to temperature separation of the purely magnetic transition, whose Curie temperature $T_C$ slowly increases with applied pressure, and the magnetostructural transition characterized by critical temperature showing much rapid decrease with increasing pressure. Comparison of the DSC data for the investigated compound and the isostructural CoMn$_{0.95}$Cu$_{0.05}$Ge one has made it possible to determine both the structural and magnetic components of entropy change.
