2009/03/25 by Rajiv R. P. Singh, Singh, Rajiv R. P. · 1 citation
Materials Science · Physics and Astronomy · #FOS: Physical sciences #Iron-based superconductors research #Strongly Correlated Electrons (cond-mat.str-el) #cond-mat.str-el
paper · pdf · doi:10.48550/arxiv.0903.4408
4 pages, one figure
arxiv created 2009/03/25 · openalex publication_date 2009/03/25 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We show that the neutron scattering spectra observed in CaFe2As2 by Zhao et al (arXiv:0903.2686v1) and the highly unusual spatially anisotropic exchange constants in the iron pnictides derived by Han et al (Phys. Rev. Lett. 102, 107003 (2009)), using electronic structure calculations, can be explained by assuming a role for orbital order in these materials. We write down a simple model Hamiltonian with tertagonal symmetry, whose spin-wave spectra describes the observed dispersion relations. We further argue that these materials have orbital selective Mott transition, which is driven by superexchange between neighboring iron atoms. We suggest that reduced spin and quasi-one dimensionality and not frustration are responsible for the reduced moments in these materials.