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arXiv · 0911.4713

Incommensurate itinerant antiferromagnetic excitations and spin resonance in the FeTe$_{0.6}$Se$_{0.4}$ superconductor

D. N. Argyriou·A. Hiess·A. Akbari·I. Eremin·M. M. Korshunov·Jin Hu·Bin Qian·Zhiqiang Mao·Yiming Qiu·Collin Broholm·W. Bao
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Abstract

We report on inelastic neutron scattering measurements that find incommensurate itinerant like magnetic excitations in the normal state of superconducting FeTe$_{0.6}$Se$_{0.4}$ (\Tc=14K) at wave-vector $\mathbf{Q}_{inc}=(1/2\pmε,1/2\mpε)$ with $ε$=0.09(1). In the superconducting state only the lower energy part of the spectrum shows significant changes by the formation of a gap and a magnetic resonance that follows the dispersion of the normal state excitations. We use a four band model to describe the Fermi surface topology of iron-based superconductors with the extended $s(\pm)$ symmetry and find that it qualitatively captures the salient features of these data.

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D. N. Argyriou, A. Hiess, A. Akbari, I. Eremin, M. M. Korshunov, Jin Hu, Bin Qian, Zhiqiang Mao, Yiming Qiu, Collin Broholm, W. Bao. 2009-11-24. Incommensurate itinerant antiferromagnetic excitations and spin resonance in the FeTe$_{0.6}$Se$_{0.4}$ superconductor. https://doi.org/10.1103/physrevb.81.220503

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