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arXiv · 0910.1318

Optical spectroscopy study on single crystalline LaFeAsO

Z. G. Chen·R. H. Yuan·T. Dong·N. L. Wang
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Abstract

Millimeter-sized single crystals of LaFeAsO were grown from NaAs flux and the in-plane optical properties were studied over a wide frequency range. A sizable electronic correlation effect was indicated from the analysis of the free-carrier spectral weight. With decreasing temperature from 300 K, we observed a continuous suppression of the spectral weight near 0.6 eV. But a spin-density-wave gap formation at lower energy scale was seen only in the broken-symmetry state. We elaborate that both the itinerancy and local spin interactions of Fe\emph{3d} electrons are present for the FeAs-based systems; however, the establishment of the long-range magnetic order at low temperature has a dominantly itinerant origin.

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Z. G. Chen, R. H. Yuan, T. Dong, N. L. Wang. 2010-03-03. Optical spectroscopy study on single crystalline LaFeAsO. https://doi.org/10.1103/physrevb.81.100502

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