2011/07/11 by Lei Hao, Chi‐Cheng Lee, Hao, Lei +4
Materials Science · Physics and Astronomy · #Iron-based superconductors research #Magnetic Properties of Alloys #Rare-earth and actinide compounds #cond-mat.mtrl-sci #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.48550/arxiv.1107.1952
5 pages, 2 figures
arxiv created 2011/07/11 · arxiv updated 2011/07/12
Double exchange mechanism is believed to favor transport along ferromagnetic directions, the failure of which in explaining the unusual resistivity anisotropy in iron pnictides is investigated. Several factors intrinsic to the microscopic mechanism of transport in iron pnictides are identified and analyzed, including the moderate Hund's coupling, low local moment, and presence of two anisotropic degenerate orbitals xz and yz. In particular, the substantial second neighbor hoppings are found to be decisive in giving results opposite to the double exchange picture. In high temperature nonmagnetic phase, orbital ordering is shown to give the right trend of resistivity anisotropy as observed experimentally, advocating its essential role in electron transport of iron pnictides.