局域态密度对铁基超导体能隙对称性的影响
Effect of Local Density of States on the Gap Symmetry in the Fe-Based Superconductors

作者: 叶晓山 :扬州大学; 马幸 , 刘拥军 :;

关键词: 能隙对称性自旋涨落局域态密度Gap Symmetry Spin Fluctuation Local Density of States.

摘要: 我们对解释新发现的铁基化合物中的超导体能隙对称性提出一个方案。这个方案是在赫伯德模型中研究反铁磁(AFM)自旋涨落调制的电子-电子耦合。我们发现在不同的费米面上超导能隙的对称性是不相同的,并且能隙节点的出现依赖准粒子的区域态密度(LDOS)。这个发现解释了ARPES和一些其他实验中的有争议的实验结果。

Abstract: We present a scenario for the gap symmetry observed in newly discovered unconventional superconduc- tivity of Fe-based layered compound .The scenario is explored in Hubbard model including electron-electron couplings mediated by antiferromagnetic(AFM) spin fluctuation . We find that the superconducting gap symmetries are different on different Fermi surfaces and the gap node emergence depends on the local density of states(LDOS) of quasi-particles .This mechanism explains the controversial experiment results oberved in the ARPES and some transport experiments .

文章引用: 叶晓山 , 马幸 , 刘拥军 (2011) 局域态密度对铁基超导体能隙对称性的影响。 现代物理, 1, 23-27. doi: 10.12677/mp.2011.11003

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