2011/06/30 by Jose Rodriguez, J. P. Rodriguez, M. A. N. Araújo +2
Materials Science · Physics and Astronomy · #Iron-based superconductors research #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.84.224504
published as Phys. Rev. B 84, 224504 (2011) · 11 pages, 3 figures, published version
openalex publication_date 2011/12/15 · arxiv created 2011/12/17 · arxiv updated 2011/12/20 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
A two-orbital t-J model over the square lattice that describes low-energy electronic excitations in iron-pnictide high-Tc superconductors is analyzed with Schwinger-boson-slave-fermion mean-field theory and by exact numerical diagonalization on a finite system. When interorbital hole hopping is suppressed, a quantum critical point (QCP) is identified that separates a commensurate spin-density wave (cSDW) state at strong Hund's rule coupling from a hidden half metal state at weak Hund's rule coupling. Low-energy spin waves that disperse anisotropically from cSDW momenta are predicted at the QCP. Nested Fermi surfaces similar to those observed experimentally in iron-pnictide materials are also predicted in such case.