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arXiv · 0804.1324

Nernst effect of the new iron-based superconductor LaO$_{1-x}$F$_{x}$FeAs

Z. W. Zhu·Z. A. Xu·X. Lin·G. H. Cao·C. M. Feng·G. F. Chen·Z. Li·J. L. Luo·N. L. Wang
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Abstract

We report the first Nernst effect measurement on the new iron-based superconductor LaO$_{1-x}$F$_{x}$FeAs $(x=0.1)$. In the normal state, the Nernst signal is negative and very small. Below $T_{c}$ a large positive peak caused by vortex motion is observed. The flux flowing regime is quite large compared to conventional type-II superconductors. However, a clear deviation of the Nernst signal from normal state background and an anomalous depression of off-diagonal thermoelectric current in the normal state between $T_{c}$ and 50 K are observed. We propose that this anomaly in the normal state Nernst effect could correlate with the SDW fluctuations.

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Z. W. Zhu, Z. A. Xu, X. Lin, G. H. Cao, C. M. Feng, G. F. Chen, Z. Li, J. L. Luo, N. L. Wang. 2008-05-29. Nernst effect of the new iron-based superconductor LaO$_{1-x}$F$_{x}$FeAs. https://doi.org/10.1088/1367-2630%2F10%2F6%2F063021

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