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arXiv · 1002.2701

Spin and Charge Dynamics Ruled by Antiferromagnetic Order in Iron Pnictides

E. Kaneshita·T. Tohyama
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Abstract

We examine the spin and charge excitations in antiferromagnetic iron pnictides by mean-field calculations with a random phase approximation in a five-band itinerant model. The calculated excitation spectra reproduce well spin-wave dispersions observed in inelastic neutron scattering, with a realistic magnetic moment for CaFe$_2$As$_2$. A particle-hole gap is found to be crucial to obtain consistent results; we predict the spin wave in LaFeAsO disappears at a lower energy than in CaFe$_2$As$_2$. We analyze that the charge dynamics to make predictions for resonant inelastic x-ray scattering spectra.

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E. Kaneshita, T. Tohyama. 2010-09-27. Spin and Charge Dynamics Ruled by Antiferromagnetic Order in Iron Pnictides. https://doi.org/10.1103/physrevb.82.094441

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