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arXiv · 0803.2405

Point-Contact Spectroscopy of Iron-Based Layered Superconductor LaO$_{0.9}$F$_{0.1-\delta}$FeAs

Lei Shan·Yonglei Wang·Xiyu Zhu·Gang Mu·Lei Fang·Cong Ren·Hai-Hu Wen
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Abstract

We present point-contact spectroscopy data for junctions between a normal metal and the newly discovered F-doped superconductor LaO$_{0.9}$F$_{0.1-\delta}$FeAs (F-LaOFeAs). A zero-bias conductance peak was observed and its shape and magnitude suggests the presence of Andreev bound states at the surface of F-LaOFeAs, which provides a possible evidence of an unconventional pairing symmetry with a nodal gap function. The maximum gap value $\Delta_0\approx3.9\pm0.7$meV was determined from the measured spectra, in good agreement with the recent experiments on specific heat and lower critical field.

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Lei Shan, Yonglei Wang, Xiyu Zhu, Gang Mu, Lei Fang, Cong Ren, Hai-Hu Wen. 2008-03-17. Point-Contact Spectroscopy of Iron-Based Layered Superconductor LaO$_{0.9}$F$_{0.1-\delta}$FeAs. https://doi.org/10.1209/0295-5075/83/57004

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