title: Theory of two-magnon Raman scattering in iron pnictides and chalcogenides.
abstract: Although the parent iron-based pnictides and chalcogenides are itinerant antiferromagnets, the use of local moment picture to understand their magnetic properties is still widespread. We study magnetic Raman scattering from a local moment perspective for various quantum spin models proposed for this new class of superconductors. These models vary greatly in the level of magnetic frustration and show a vastly different two-magnon Raman response. Light scattering by two-magnon excitations thus provides a robust and independent measure of the underlying spin interactions. In accord with other recent experiments, our results indicate that the amount of magnetic frustration in these systems may be small.
authors.affiliation: Stanford Institute for Materials and Energy Science, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: C-C
authors.initials: CC
authors.lastname: Chen
authors.forename: C J
authors.initials: CJ
authors.lastname: Jia
authors.forename: A F
authors.initials: AF
authors.lastname: Kemper
authors.forename: R R P
authors.initials: RR
authors.lastname: Singh
authors.forename: T P
authors.initials: TP
authors.lastname: Devereaux