High-resolution photoemission study of MgB2

被引：134

作者：

Takahashi, T

Sato, T

Souma, S

Muranaka, T

Akimitsu, J

机构：

[1] Tohoku Univ, Dept Phys, Sendai, Miyagi 9808578, Japan

[2] Aoyama Gakuin Univ, Dept Phys, Setagaya Ku, Tokyo 1578572, Japan

来源：

PHYSICAL REVIEW LETTERS | 2001年 / 86卷 / 21期

关键词：

D O I：

10.1103/PhysRevLett.86.4915

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We have performed high-resolution photoemission spectroscopy on MgB2 and observed opening of a superconducting gap with a narrow coherent peak. We found that the superconducting gap is s like with the gap value (Delta) of 4.5 +/- 0.3 meV at 15 K. The temperature dependence (15-40 K) of the gap value follows well the BCS form, suggesting that 2 Delta /k(B)T(c) at T = 0 is about 3. No pseudogap behavior is observed in the normal state. The present results strongly suggest that MgB2 is categorized into a phonon-mediated BCS superconductor in the weak-coupling regime.

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页码：4915 / 4917

页数：3

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