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arXiv · 0910.0898

Band and momentum dependent electron dynamics in superconducting ${\rm Ba(Fe_{1-x}Co_{x})_2As_2}$ as seen via electronic Raman scattering

B. Muschler·W. Prestel·R. Hackl·T. P. Devereaux·J. G. Analytis·Jiun-Haw Chu·I. R. Fisher
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Abstract

We present details of carrier properties in high quality ${\rm Ba(Fe_{1-x}Co_{x})_2As_2}$ single crystals obtained from electronic Raman scattering. The experiments indicate a strong band and momentum anisotropy of the electron dynamics above and below the superconducting transition highlighting the importance of complex band-dependent interactions. The presence of low energy spectral weight deep in the superconducting state suggests a gap with accidental nodes which may be lifted by doping and/or impurity scattering. When combined with other measurements, our observation of band and momentum dependent carrier dynamics indicate that the iron arsenides may have several competing superconducting ground states.

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B. Muschler, W. Prestel, R. Hackl, T. P. Devereaux, J. G. Analytis, Jiun-Haw Chu, I. R. Fisher. 2009-10-06. Band and momentum dependent electron dynamics in superconducting ${\rm Ba(Fe_{1-x}Co_{x})_2As_2}$ as seen via electronic Raman scattering. https://doi.org/10.1103/physrevb.80.180510

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