Unique interplay between superconducting and ferromagnetic orders in EuRbFe${}_4$As${}_4$

V. S. Stolyarov, A. Casano, M. A. Belyanchikov +15

Transport, magnetic and optical investigations on EuRbFe${}_4$As${}_4$ single crystals evidence that the ferromagnetic ordering of the Eu${}^{2+}$ magnetic moments at $T_N=15$ K, below t…