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arXiv 0709.1246cond-mat.supr-concond-mat.str-el
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重费米子超导体的Andreev反射和CeCoIn_5的序参量对称性

Andreev Reflection in Heavy-Fermion Superconductors and Order Parameter Symmetry in CeCoIn_5

W. K. Park, J. L. Sarrao, J. D. Thompson, L. H. Greene

摘要:

微分电导谱从纳米结上的重费米子超导体CeCoIn $_5$沿三个主要的晶体取向。连接点之间特征的一致性和可重复性确保了它们的光谱性质。所有的结都表现出类似的电导不对称性和Andreev反射式电导,信号降低(约10%-13%),这两种情况在重费米子超导体结中都很常见。使用扩展的Blonder-Tinkham-Klapwijk模型的分析表明,我们的数据提供了$d_{x^2-y^2}$对称性的第一个光谱证据。为了量化我们的电导谱,我们提出了一个模型,考虑在重费米子的一般现象,双流体的行为,和能量依赖的态密度。我们的模型非常适合实验数据,应该激励进一步的研究。

英文摘要:

Differential conductance spectra are obtained from nanoscale junctions on the heavy-fermion superconductor CeCoIn$_5$ along three major crystallographic orientations. Consistency and reproducibility of characteristic features among the junctions ensure their spectroscopic nature. All junctions show a similar conductance asymmetry and Andreev reflection-like conductance with reduced signal (~ 10%-13%), both commonly observed in heavy-fermion superconductor junctions. Analysis using the extended Blonder-Tinkham-Klapwijk model indicates that our data provide the first spectroscopic evidence for $d_{x^2-y^2}$ symmetry. To quantify our conductance spectra, we propose a model by considering the general phenomenology in heavy fermions, the two-fluid behavior, and an energy-dependent density of states. Our model fits to the experimental data remarkably well and should invigorate further investigations.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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