Phase diagram of the isovalent phosphorous-substituted 122-type iron pnictides

Abstract

Recent experiments demonstrated that isovalent doping system gives the similar phase diagram as the heterovalent doped cases. For example, with the phosphorous (P)-doping, the magnetic order in BaFe$_{2}$(As$_{1-x}$P$_{x}$)$_{2}$ compound is first suppressed, then the superconductivity dome emerges to an extended doping region but eventually it disappears at large $x$. With the help of a minimal two-orbital model for both BaFe$_{2}$As$_{2}$ and BaFe$_{2}$P$_{2}$, together with the self-consistent lattice Bogoliubov-de Gennes (BdG) equation, we calculate the phase diagram against the P content $x$ in which the doped isovalent P-atoms are treated as impurities. We show that our numerical results can qualitatively compare with the experimental measurements.