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arXiv · 1212.4946

Measurement of Coherent Polarons in the Strongly Coupled Antiferromagnetically Ordered Iron-Chalcogenide Fe1.02Te using Angle-Resolved Photoemission Spectroscopy

Zhongkai Liu·Ruihua He·Donghui Lu·Ming Yi·Yulin Chen·Makoto Hashimoto·Robert G. Moore·Sung-Kwan Mo·Elizabeth A. Nowadnick·Jin Hu·Tijiang Liu·Zhiqiang Mao·Thomas P. Devereaux·Zahid Hussain·Zhi-Xun Shen
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Abstract

The nature of metallicity and the level of electronic correlations in the antiferromagnetically ordered parent compounds are two important open issues for the iron-based superconductivity. We perform a temperature-dependent angle-resolved photoemission spectroscopy study of Fe1.02Te, the parent compound for iron chalcogenide superconductors. Deep in the antiferromagnetic state, the spectra exhibit a "peak-dip-hump" line shape associated with two clearly separate branches of dispersion, characteristics of polarons seen in manganites and lightly-doped cuprates. As temperature increases towards the Neel temperature (T_N), we observe a decreasing renormalization of the peak dispersion and a counterintuitive sharpening of the hump linewidth, suggestive of an intimate connection between the weakening electron-phonon (e-ph) coupling and antiferromagnetism. Our finding points to the highly-correlated nature of Fe1.02Te ground state featured by strong interactions among the charge, spin and lattice and a good metallicity plausibly contributed by the coherent polaron motion.

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Zhongkai Liu, Ruihua He, Donghui Lu, Ming Yi, Yulin Chen, Makoto Hashimoto, Robert G. Moore, Sung-Kwan Mo, Elizabeth A. Nowadnick, Jin Hu, Tijiang Liu, Zhiqiang Mao, Thomas P. Devereaux, Zahid Hussain, Zhi-Xun Shen. 2012-12-20. Measurement of Coherent Polarons in the Strongly Coupled Antiferromagnetically Ordered Iron-Chalcogenide Fe1.02Te using Angle-Resolved Photoemission Spectroscopy. https://doi.org/10.1103/physrevlett.110.037003

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