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arXiv · 0907.0186

Optical study on the spin-density wave properties in single crystalline Na$_{1-\delta}$FeAs

W. Z. Hu·G. Li·P. Zheng·G. F. Chen·J. L. Luo·N. L. Wang
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Abstract

We report an optical investigation on the in-plane charge dynamics for Na$_{1-\delta}$FeAs single crystal. A clear optical evidence for the spin-density wave (SDW) gap is observed. As the structural/magnetic transitions are separated in the Na$_{1-\delta}$FeAs case, we find the SDW gap opens in accordance with the magnetic transition. Comparing with the optical response of other FeAs-based parent compounds, both the gap value 2$\Delta$ and the energy scale for the gap-induced spectral weight redistribution are smaller in Na$_{1-\delta}$FeAs. Our findings support the itinerant origin of the antiferromagnetic transition in the FeAs-based system.

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W. Z. Hu, G. Li, P. Zheng, G. F. Chen, J. L. Luo, N. L. Wang. 2009-07-01. Optical study on the spin-density wave properties in single crystalline Na$_{1-\delta}$FeAs. https://doi.org/10.1103/physrevb.80.100507

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