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arXiv · 0909.3352

Dual Character of Magnetism in Ferropnictides: Insights from Optical Measurements

S. J. Moon·J. H. Shin·D. Parker·W. S. Choi·I. I. Mazin·Y. S. Lee·J. Y. Kim·N. H. Sung·B. K. Cho·S. H. Khim·J. S. Kim·K. H. Kim·T. W. Noh
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Abstract

We investigate the electronic structure of EuFe$_{2}$As$_{2}$ using optical spectroscopy and first-principles calculations. At low temperature we observe the evolution of \textit{two} gap-like features, one having a BCS mean-field behavior and another with strongly non-BCS behavior. Using band structure calculations, we identify the former with a spin-Peierls-like partial gap in $d_{yz}$ bands, and the latter with the transition across the large exchange gap in $d_{xz}/d_{xy}$ bands. Our results demonstrate that the antiferromagnetism in the ferropnictides is neither fully local nor fully itinerant, but contains elements of both.

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S. J. Moon, J. H. Shin, D. Parker, W. S. Choi, I. I. Mazin, Y. S. Lee, J. Y. Kim, N. H. Sung, B. K. Cho, S. H. Khim, J. S. Kim, K. H. Kim, T. W. Noh. 2009-09-18. Dual Character of Magnetism in Ferropnictides: Insights from Optical Measurements. https://arxiv.org/abs/0909.3352

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