Ferromagnetic Superconductors

Superconductivity and ferromagnetism in EuFe2(As1−xPx)2

“…[4] Earlier experiments revealed the incompatible nature of the two collective phenomena in (La,Gd) and (Ce, Pr)Ru 2 solid solutions. [5] Until late 1970s possible coexistence of SC and FM was evidenced in ErRh 4 B 4 [6] and Ho 1.2 Mo 6 S 8 [7], only under narrow regimes of temperature and external field. The interplay of SC and magnetic ordering was also exhibited in a family of layered compounds RNi 2 B 2 C (R=Tm, Er, Ho and Dy) [8] and ruthenocuprates [9,10].…”

59Co-NMR/Nuclear-Quadrupole-Resonance (NQR) Studies on Ferromagnetic Superconductor UCoGe

“…1) One of the well-known examples is (Ce 1−x Gd x )Ru 2 , in which ferromagnetic ordering occurs in the superconducting (SC) state. 2) In the compounds, ferromagnetism originates from the Gd 4 f electrons and superconductivity is ascribed to the Ru site, since superconductivity is significantly suppressed by impurity-doping at the Ru site. 3) Coexistence has been also reported in rare-earth ternary compounds such as HoNi 2 B 2 C. 4) However, breakthrough was reported in 2000: superconductivity was discovered in ferromagnet UGe 2 at high pressure.…”

Superconductivity and Magnetism of Dy1-xYxRh4B4: Candidate for Spin-Triplet Cooper Pairing

“…Significant, and apparently the first, experimental works on this problem have been made in 1958 and presented in few papers, which have followed one after another [1,2]. In them the important role of a spin subsystem in the organization of a superconducting pairing in magnetic superconductors has been found out (instead of the effective magnetic moments of the rare-earth elements).…”