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arXiv · 0909.1195

First-principles-based $\pm s$-wave modelling for iron-based superconductors:Studies for specific heat and nuclear magnetic relaxation rate

N. Nakai·H. Nakamura·Y. Ota·Y. Nagai·N. Hayashi·M. Machida
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Abstract

In order to consistently explain controversial experimental results on superconducting states observed by different probes in typical iron-based superconductors, we construct a realistic multi-band $\pm s$-wave pairing model by combining the quasiclassical formalism with the first-principles calculation. The model successfully resolves the controversies in contrast to the fact that simplified models such as two-band $\pm s$-wave one fail to do. A key in the model is the existence of relatively small gaps which leads to material-dependent peculiarities.

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N. Nakai, H. Nakamura, Y. Ota, Y. Nagai, N. Hayashi, M. Machida. 2009-09-07. First-principles-based $\pm s$-wave modelling for iron-based superconductors:Studies for specific heat and nuclear magnetic relaxation rate. https://doi.org/10.1103/physrevb.82.094501

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