A universal (almost) phase diagram for iron pnictide superconductors

A recent preprint from Ni, Thaler, Kracher, Yan, Budko, and Canfield (Ames Lab, Iowa State) reports the above phase diagram for members of the 122 family (based on the parent compound BaFe2As2). When doped with transition metals the antiferromagnetic transition is suppressed and superconductivity appears below the lower dome. Near the antiferromagnetic transition there is also a structural transition from a tetragonal to an orthorhombic crystal structure.

Comments

  1. UnknownJune 19, 2009 at 4:15 AM

    It is probably worth pointing out that something similar has already appeared in PRB for SrBa2As2: S. R. Saha, et. al. PRB 79, 224519 (2009), Fig. 9.

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