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arXiv · 0908.4361

Spin-Phonon Coupling in Iron Pnictide Superconductors

T. Egami·B. V. Fine·D. J. Singh·D. Parshall·C. de la Cruz·P. Dai
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Abstract

The magnetic moment in the parent phase of the iron-pnictide superconductors varies with composition even when the nominal charge of iron is unchanged. We propose the spin-lattice coupling due to the magneto-volume effect as the primary origin of this effect, and formulate a Landau theory to describe the dependence of the moment to the Fe-As layer separation. We then compare the superconductive critical temperature of doped iron pnictides to the local moment predicted by the theory, and suggest that the spin-phonon coupling may play a role in the superconductivity of this compound.

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T. Egami, B. V. Fine, D. J. Singh, D. Parshall, C. de la Cruz, P. Dai. 2009-08-29. Spin-Phonon Coupling in Iron Pnictide Superconductors. https://doi.org/10.1016/j.physc.2009.11.167

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