Departamento de Física de la Materia Condensada and Instituto de Ciencia de Materiales de Aragón, CSIC-Universidad de Zaragoza, 50009 Zaragoza, Spain.
J Phys Condens Matter. 2014 Apr 16;26(15):156001. doi: 10.1088/0953-8984/26/15/156001. Epub 2014 Mar 27.
X-ray magnetic circular dichroism (XMCD), longitudinal (χac) and transverse (TS) ac magnetic susceptibility have been measured in the RCo2 series (R = Ho, and Tm) as a function of temperature and applied magnetic field. We show that parimagnetism is a general behavior among the RCo2 ferrimagnetic series (R being a heavy rare-earth ion). XMCD results supply evidence of the presence of two compensation temperatures above Tc, defining two different parimagnetic configurations, which is a fully unexpected result. The inverse χ'ac curve exhibits a small anomaly which vanishes under low applied magnetic fields. The combination of TS and XMCD measurements allows one to depict new magnetic phase diagrams for these compounds of the RCo2 series. A new scenario allowing one to understand the observed phenomenology as a Griffiths phase-like behavior is proposed, where the amorphous RCo2 represents the undiluted system case.
X 射线磁圆二色性（XMCD）、纵向（χac）和横向（TS）交流磁化率已在 RCo2 系列（R = Ho 和 Tm）中作为温度和外加磁场的函数进行了测量。我们表明，亚铁磁系列中的 RCo2 反铁磁（R 为重稀土离子）是普遍的行为。XMCD 结果提供了存在两个补偿温度高于 Tc 的证据，定义了两种不同的反铁磁构型，这是一个完全出乎意料的结果。反 χ'ac 曲线表现出一个小的异常，在施加低磁场时消失。TS 和 XMCD 测量的结合允许为这些 RCo2 系列化合物描绘新的磁相图。提出了一种新的方案，允许将观察到的现象理解为类似于格里菲斯相的行为，其中非晶态 RCo2 代表未稀释系统的情况。
