PHYSICS
A robust coexistence of superconductivity and ferromagnetism
Superconductivity (SC) and ferromagnetism (FM) are mutually antagonistic,and generally incompatible in a single material.It takes over half a century to seek a ferromagnetic superconductor (FMSC),in which SC coexists with FM below their transition temperatures (Tsc and TFM,with Tsc > TFM).However,a genuine FMSC that exhibits robust superconducting and ferromagnetic properties has been absent until very recently.Guang-Han Cao and co-workers from Zhejiang University reported experimental observations of bulk SC at ~35 K and full FM at ~ 15 K in AEuFe4As4 (A =Rb,Cs).The special iron pnictides consist of FeAs superconductive layers,Eu magnetic layers and Rb/Cs non-magnetic layers.