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arXiv · 1012.3254

Theory of two magnon Raman scattering in antiferromagnetic iron pnictides

C. -C. Chen·C. J. Jia·A. F. Kemper·R. R. P. Singh·T. P. Devereaux
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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.

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C. -C. Chen, C. J. Jia, A. F. Kemper, R. R. P. Singh, T. P. Devereaux. 2011-02-10. Theory of two magnon Raman scattering in antiferromagnetic iron pnictides. https://doi.org/10.1103/physrevlett.106.067002

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