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arXiv · 1703.06601

Spin-wave excitations in the SDW state of doped iron pnictides

Dheeraj Kumar Singh
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Abstract

We investigate the spin-wave excitations in the spin-density wave state of doped iron pnictides within a five-orbital model. We find that the excitations along ($π, 0$)$\rightarrow$($π, π$) are very sensitive to the doping whereas they do not exhibit a similar sensitivity along ($0, 0$) $\rightarrow$ ($π, 0$). Secondly, anisotropy in the excitations around ($π, 0$) with an elliptical shape grows on moving towards the hole-doped region for low energy, whereas it decreases for the high-energy excitations on the contrary. Thirdly, spin-wave spectral weight shifts towards the low-energy region on moving away from zero doping. We find these features to be in qualitative agreement with the inelastic neutron-scattering measurements for the doped pnictides.

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Dheeraj Kumar Singh. 2017-03-20. Spin-wave excitations in the SDW state of doped iron pnictides. https://doi.org/10.1088/1361-648x%2Faa7e13

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