A new ferromagnetic superconductor: \(\hbox {CsEuFe}_4\hbox {As}_4\)

一种新的铁磁超导体: CsEuFe4As4


Superconductivity (SC) and ferromagnetism (FM) are in general antagonistic, which makes their coexistence very rare. Following our recent discovery of robust coexistence of SC and FM in \(\hbox {RbEuFe}_4\hbox {As}_4\) (Liu et al. in Phys Rev B 93:214503, 2016), here we report another example of such a coexistence in its sister compound \(\hbox {CsEuFe}_4\hbox {As}_4\), synthesized for the first time. The new material exhibits bulk SC at 35.2 K and \(\hbox {Eu}^{2+}\)-spin ferromagnetic ordering at 15.5 K, demonstrating that it is a new robust ferromagnetic superconductor.


超导电性与铁磁性是两种相互对立的物理现象: 超导体具有完全抗磁性, 而铁磁体则产生自发磁化, 两者很难共存。本文报道一种新型磁性超导体 CsEuFe4As4, 其晶体结构由FeAs超导层、非磁 Cs 单原子层以及磁性 Eu 单原子层沿 c 轴交替排列。实验测量表明, 该材料在35.2K以下显示出大块超导电性。在15.5 K以下, Eu2+ 离子自旋呈铁磁排列, 超导与之共存。因此, CsEuFe4As4 是一种罕见的超导与铁磁共存的铁磁铁基超导体。

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This work was supported by the National Natural Science Foundation of China (11474252, 90922002 and 11190023) and the National Basic Research Program of China (2012CB821404).

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Correspondence to Guang-Han Cao.

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Liu, Y., Liu, YB., Chen, Q. et al. A new ferromagnetic superconductor: \(\hbox {CsEuFe}_4\hbox {As}_4\) . Sci. Bull. 61, 1213–1220 (2016). https://doi.org/10.1007/s11434-016-1139-2

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  • Superconductivity
  • Ferromagnetism
  • Iron-based superconductors