Lack of superconductivity in the phase diagram of single-crystalline $\mathrm{Eu}{\left(\mathrm{F}{\mathrm{e}}_{1-x}\mathrm{C}{\mathrm{o}}_x\right)}_2\mathrm{A}{\mathrm{s}}_2$ grown by transition metal arsenide flux

Journal Article · 02 October 2018 · Physical Review Materials

DOI: https://doi.org/10.1103/PhysRevMaterials.2.104801 · OSTI ID:1478231

Wang, Gang ^[1]; Meier, William R. ^[2]; Straszheim, Warren E. ^[3]; Slagle, Joshua ^[2]; Bud’ko, Sergey L. ^[2]; Canfield, Paul C. ^[2]

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1. Ames Lab. and Iowa State Univ., Ames, IA (United States); Chinese Academy of Sciences (CAS), Beijing (China)
2. Ames Lab. and Iowa State Univ., Ames, IA (United States)
3. Iowa State Univ., Ames, IA (United States)

Here, the interplay of magnetism and superconductivity (SC) has been a focus of interest in condensed matter physics for decades. EuFe₂As₂ has been identified as a potential platform to investigate interactions between structural, magnetic, and electronic effects as well as the coexistence of magnetism and SC with similar transition temperatures. However, there are obvious inconsistencies in the reported phase diagrams of Eu(Fe_1–xCo_x)₂As₂ crystals grown by different methods. For transition metal arsenide (TMA)-flux-grown crystals, even the existence of SC is uncertain. Here we reexamine the phase diagram of single-crystalline Eu(Fe_1–xCo_x)₂As₂ grown by TMA flux. We found that the lattice parameter c shrinks linearly with Co doping, almost twice as fast as that of the tin-flux-grown crystals. With Co doping, the spin-density-wave (SDW) order of the Fe sublattice is quickly suppressed, being detected only up to x=0.08. The magnetic ordering temperature of the Eu²⁺ sublattice (T_Eu) shows a systematic evolution with Co doping, first going down and reaching a minimum at x=0.08, then increasing continuously up to x=0.24. Over the whole composition range investigated, no signature of SC is observed above 1.8 K.

• Research Organization: Ames Laboratory (AMES), Ames, IA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: AC02-07CH11358; 51832010; 51572291; 51322211; GBMF4411
• OSTI ID: 1478231
• Alternate ID(s): OSTI ID: 1475233
• Report Number(s): IS-J-9779; PRMHAR
• Journal Information: Physical Review Materials, Vol. 2, Issue 10; ISSN 2475-9953
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English