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arXiv 1106.4585cond-mat.supr-con
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SrPd2Ge2中常规超导性的证据

Evidence for conventional superconductivity in SrPd2Ge2

T. K. Kim, A. N. Yaresko, V. B. Zabolotnyy, A. A. Kordyuk, D. V. Evtushinsky, N. H. Sung, B. K. Cho, T. Samuely, P. Szabó, J. G. Rodrigo, J. T. Park, D. S. Inos… 展开作者

T. K. Kim, A. N. Yaresko, V. B. Zabolotnyy, A. A. Kordyuk, D. V. Evtushinsky, N. H. Sung, B. K. Cho, T. Samuely, P. Szabó, J. G. Rodrigo, J. T. Park, D. S. Inosov, P. Samuely, B. Büchner, S. V. Borisenko

摘要:

用角分辨光电子能谱(ARPES)、扫描隧道能谱(STS)和局域密度近似(LDA)的能带计算方法研究了SrPd_2Ge_2单晶的电子结构。STS测量表明,单s波超导能隙Δ(0)= 0.5 meV。所观察到的费米表面的光子能量依赖性揭示了一个强烈的三维字符的相应的电子带。通过比较实验测量和计算的费米速度的重整化因子为0.95,这是远远小于在铁基超导体报道的典型值。我们将这种异常的低能带重正化归因于传导电子的不同轨道特征,并利用ARPES和STS数据认为SrPd_2Ge_2可能是一种常规超导体,这使得它明显不同于“122”家族的同构铁磷属元素化物超导体。

英文摘要:

Electronic structure of SrPd2Ge2 single crystals is studied by angle-resolved photoemission spectroscopy (ARPES), scanning tunneling spectroscopy (STS) and band-structure calculations within the local-density approximation (LDA). The STS measurements show single s-wave superconducting energy gap Δ(0) = 0.5 meV. Photon-energy dependence of the observed Fermi surface reveals a strongly three-dimensional character of the corresponding electronic bands. By comparing the experimentally measured and calculated Fermi velocities a renormalization factor of 0.95 is obtained, which is much smaller than typical values reported in Fe-based superconductors. We ascribe such an unusually low band renormalization to the different orbital character of the conduction electrons and using ARPES and STS data argue that SrPd2Ge2 is likely to be a conventional superconductor, which makes it clearly distinct from isostructural iron pnictide superconductors of the "122" family.

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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