Direct observation of superconducting gaps in MgB2 by angle-resolved photoemission spectroscopy

被引：1
作者：
Souma, S
Machida, Y
Sato, T
Takahashi, T
Matsui, H
Wang, SC
Ding, H
Kaminski, A
Campuzano, JC
Sasaki, S
Kadowaki, K
机构：
[1] Tohoku Univ, Dept Phys, Sendai, Miyagi 9808578, Japan
[2] Tokyo Inst Technol, Mat & Struct Lab, Yokohama, Kanagawa 2268503, Japan
[3] Boston Coll, Dept Phys, Chestnut Hill, MA 02467 USA
[4] Univ Illinois, Dept Phys, Chicago, IL 60607 USA
[5] Univ Tsukuba, Inst Mat Sci, Tsukuba, Ibaraki 3058573, Japan
来源：
PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS | 2004年 / 408卷
关键词：
MgB2; ARPES;
D O I：
10.1016/j.physc.2004.02.054
中图分类号：
O59 [应用物理学];
学科分类号：
摘要：
High-resolution angle-resolved photoemission spectroscopy has been carried out to clarify the anomalous superconductivity of MgB2. We observed three bands crossing the Fermi level, which are ascribed to B2p-sigma, pi and surface bands. We have succeeded for the first time in directly observing the superconducting gaps of these bands separately. We have found that the superconducting-gap sizes of sigma and surface bands are 6.5 +/- 0.5 and 6.0 +/- 0.5 meV, respectively, while that of the pi band is much smaller (1.5 +/- 0.5 meV). The present experimental result unambiguously demonstrates the validity of the two-band superconductivity in MgB2. (C) 2004 Published by Elsevier B.V.
引用
收藏
页码：102 / 103
页数：2
相关论文
共 8 条
[1]   Specific heat of Mg11B2:: Evidence for a second energy cap -: art. no. 047001 [J].
Bouquet, F ;
Fisher, RA ;
Phillips, NE ;
Hinks, DG ;
Jorgensen, JD .
PHYSICAL REVIEW LETTERS, 2001, 87 (04) :47001-1
[2]   Review of the superconducting properties of MgB2 [J].
Buzea, C ;
Yamashita, T .
SUPERCONDUCTOR SCIENCE & TECHNOLOGY, 2001, 14 (11) :R115-R146
[3]   Strange quark polarization of the nucleon: A parameter-independent prediction of the chiral potential model [J].
Chen, XB ;
Chen, XS ;
Wang, F .
PHYSICAL REVIEW LETTERS, 2001, 87 (01)
[4]   The origin of the anomalous superconducting properties of MgB2 [J].
Choi, HJ ;
Roundy, D ;
Sun, H ;
Cohen, ML ;
Louie, SG .
NATURE, 2002, 418 (6899) :758-760
[5]   Ambient-pressure synthesis of single-crystal MgB2 and their superconducting anisotropy -: art. no. 094507 [J].
Machida, Y ;
Sasaki, S ;
Fujii, H ;
Furuyama, M ;
Kakeya, I ;
Kadowaki, K .
PHYSICAL REVIEW B, 2003, 67 (09)
[6]   Superconductivity at 39 K in magnesium diboride [J].
Nagamatsu, J ;
Nakagawa, N ;
Muranaka, T ;
Zenitani, Y ;
Akimitsu, J .
NATURE, 2001, 410 (6824) :63-64
[7]   Evidence for two superconducting energy gaps in MgB2 by point-contact spectroscopy -: art. no. 137005 [J].
Szabó, P ;
Samuely, P ;
Kacmarcík, J ;
Klein, T ;
Marcus, J ;
Fruchart, D ;
Miraglia, S ;
Marcenat, C ;
Jansen, AGM .
PHYSICAL REVIEW LETTERS, 2001, 87 (13)
[8]   Evidence for a multiple superconducting gap in MgB2 from high-resolution photoemission spectroscopy -: art. no. 177006 [J].
Tsuda, S ;
Yokoya, T ;
Kiss, T ;
Takano, Y ;
Togano, K ;
Kito, H ;
Ihara, H ;
Shin, S .
PHYSICAL REVIEW LETTERS, 2001, 87 (17) :177006-1
1