Interplay of antiferromagnetism, ferromagnetism, and superconductivity in EuFe2(As1−xP

H. S. Jeevan

¹

,

Deepa Kasinathan

²

,

H. Rösner

³

et al.

Abstract

We report a systematic study of the influence of antiferromagnetic and ferromagnetic phases of Eu 2+ moments on the superconducting phase upon doping the As site by isovalent P, which essentially acts like chemical pressure on EuFe 2 As 2 . Bulk superconductivity with transition temperatures of 22 and 28 K are observed for x = 0.16 and 0.20 samples, respectively. The Eu ions order antiferromagnetically for x 0.13, while bulk superconductivity coexists with Eu-antiferromagnetism for 0.13 < x < 0.22. In contrast, a crossover is observed for x 0.22 whereupon the Eu ions order ferromagnetically and superconductivity is fully suppressed. Densityfunctional-theory-based calculations reproduce the observed experimental findings consistently. We discuss in detail the coexistence of superconductivity and magnetism in a tiny region of the phase space and comment on the competition of ferromagnetism and superconductivity in the title compound.

Fluence-dependent femtosecond quasiparticle and Eu2+ spin relaxation dynamics in EuFe2(As,P)Pogrebna1, Mertelj2, Cao3 et al. 2016Phys. Rev. B1100View full textAdd to dashboardCite

“…The T -dependent relaxation in doped EuP-122 is qualitatively similar to Eu-122 suggesting the presence of the magnetostructural SDW transition at T SDW ∼ 35 K, consistent with the reported phase diagrams [8,12,20]. The decrease of the relative charge gap magnitude 2 (0)/k B T SDW with SDW suppression upon P doping is similar as in the Ba(Fe,Co) 2 As 2 [16].…”

“…In the iron-based superconductors family [1,2] EuFe 2 (As,P) 2 [3] and Eu(Fe,Co) 2 As 2 [4] offer an interesting experimental possibility to study the competition between the ferromagnetic (FM) and superconducting (SC) order parameters that can lead to nonuniform magnetic and SC states [4][5][6][7], since the optimal critical temperature T c ∼ 28 K [8] is comparable to the Eu 2+ spin ordering temperatures T M ∼ 20 K [3,9].…”

Magnetic structure of theEu2+moments in superconductingEuFe2(As1−xNandi1, Jin2, Xiao3 et al. 2014Phys. Rev. BSelf Cite407320View full textAdd to dashboardCite

“…Doping as well as external pressure lead to a decrease of both the structural and Fe magnetic phase transition temperatures and eventually superconductivity appears when both transitions are suppressed enough [9]. Upon P-doping, the ordering temperature of the Eu 2+ moments initially decreases by a few Kelvin until the superconductivity appears and then increases up to 30 K as the doping is increased further [20].…”

Effects of c/a Anisotropy and Local Crystal Structure on Superconductivity in AFe2(As1−xPx)2 (A = Ba1−ySry, Sr1−yCay and Eu)

“…In the annealed crystals of the Eu122P system, the magnetic order of Eu 2+ 4 f moments occurs at around T N =17-24 K, which was observed in the present crystals and also reported previously. 19) According to a previous report, 30) for Eu122P, the magnetic moments of the Eu 2+ ions aligned along the a direction antiferromagnetically are canted, yielding a ferromagnetic contribution along the c-direction.…”