The determination of the electron-phonon interaction from tunneling data in the two-band superconductor MgB2

被引：5
作者：
Daghero, D
Gonnelli, RS
Ummarino, GA
Dolgov, OV
Kortus, J
Golubov, AA
Shulga, SV
机构：
[1] Politecn Torino, Dipartimento Fis, INFM, LaTEST Lab, I-10129 Turin, Italy
[2] Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany
[3] Univ Twente, Dept Appl Phys, NL-7500 AE Enschede, Netherlands
[4] Inst Festkorper & Werkstofforschung, Dresden, Germany
来源：
PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS | 2004年 / 408卷
关键词：
electron-phonon interaction; Eliashberg equations; magnesium diboride;
D O I：
10.1016/j.physc.2004.02.098
中图分类号：
O59 [应用物理学];
学科分类号：
摘要：
We calculate the tunneling density of states (DOS) of MgB2 for different tunneling directions, by directly solving the real-axis, two-band Eliashberg equations (EE). Then we show that the numeric inversion of the standard single-band EE, if applied to the DOS of the two-band superconductor MgB2, may lead to wrong estimates of the strength of certain phonon branches (e.g. the E-2g) in the extracted electron-phonon spectral function alpha(2)F(omega). The fine structures produced by the two-band interaction turn out to be clearly observable only for tunneling along the ab-planes in high-quality single crystals. The results are compared to recent experimental data. (C) 2004 Elsevier B.V. All rights reserved.
引用
收藏
页码：353 / 354
页数：2
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