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arXiv · 1409.4051

Soft striped magnetic fluctuations competing with superconductivity in Fe_{1+x}Te

C. Stock·E. E. Rodriguez·O. Sobolev·J. A. Rodriguez-Rivera·R. A. Ewings·J. W. Taylor·A. D. Christianson·M. A. Green
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Abstract

Neutron spectroscopy is used to investigate the magnetic fluctuations in Fe_{1+x}Te - a parent compound of chalcogenide superconductors. Incommensurate "stripe-like" excitations soften with increased interstitial iron concentration. The energy crossover from incommensurate to stripy fluctuations defines an apparent hour-glass dispersion. Application of sum rules of neutron scattering find that the integrated intensity is inconsistent with an S=1 Fe^{2+} ground state and significantly less than S=2 predicted from weak crystal field arguments pointing towards the Fe^{2+} being in a superposition of orbital states. The results suggest that a highly anisotropic order competes with superconductivity in chalcogenide systems.

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C. Stock, E. E. Rodriguez, O. Sobolev, J. A. Rodriguez-Rivera, R. A. Ewings, J. W. Taylor, A. D. Christianson, M. A. Green. 2014-09-14. Soft striped magnetic fluctuations competing with superconductivity in Fe_{1+x}Te. https://doi.org/10.1103/physrevb.90.121113

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