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arXiv · 0912.0692

Antiferromagnetic fluctuations in the normal state of LiFeAs

P. Jeglic·A. Potocnik·M. Klanjsek·M. Bobnar·M. Jagodic·K. Koch·H. Rosner·S. Margadonna·B. Lv·A. M. Guloy·D. Arcon
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Abstract

We present a detailed study of 75As NMR Knight shift and spin-lattice relaxation rate in the normal state of stoichiometric polycrystalline LiFeAs. Our analysis of the Korringa relation suggests that LiFeAs exhibits strong antiferromagnetic fluctuations, if transferred hyperfine coupling is a dominant interaction between 75As nuclei and Fe electronic spins, whereas for an on-site hyperfine coupling scenario, these are weaker, but still present to account for our experimental observations. Density-functional calculations of electric field gradient correctly reproduce the experimental values for both 75As and 7Li sites.

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P. Jeglic, A. Potocnik, M. Klanjsek, M. Bobnar, M. Jagodic, K. Koch, H. Rosner, S. Margadonna, B. Lv, A. M. Guloy, D. Arcon. 2009-12-03. Antiferromagnetic fluctuations in the normal state of LiFeAs. https://doi.org/10.1103/physrevb.81.140511

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