Magnetic and pairing properties of a two-orbital model for the pnictide superconductors: A quantum Monte Carlo study

Abstract

Using the constrained-path Monte Carlo method, a two-orbital model for the pnictide superconductors is studied at half filling and in both the electron- and hole-doped cases. At half filling, a stable $(\pi ,0)$/$(0,\pi )$ magnetic order is explicitly observed, and the system tends to be in an orthomagnetic order rather than the striped antiferromagnetic order when increasing the Coulomb repulsion $U$. In the electron-doped case, the $(\pi ,0)$/$(0,\pi )$ magnetic order is enhanced upon doping and suppressed eventually, and a $s_{\pm }$ pairing state dominates all the possible nearest-neighbor-bond pairings. Whereas in the hole-doped case, the magnetic order is straightforwardly suppressed and two nearly degenerate $A_{1g}$ and $B_{1g}$ intraband pairings become the dominant ones.

8 pages, 8 figures

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Cited by in corpus (2)

• Orbital-selective Mott phases of a one-dimensional three-orbital Hubbard model studied using computational techniques
• Temperature and doping dependence of normal state spectral properties in a two-orbital model for ferropnictides