Alkali metal substitution effects in Mg1-xAxB2 (A = Li and Na)

被引：39

作者：

Li, SY ^{[1
]}

Xiong, YM ^{[1
]}

Mo, WQ ^{[1
]}

Fan, R ^{[1
]}

Wang, CH ^{[1
]}

Luo, XG ^{[1
]}

Sun, Z ^{[1
]}

Zhang, HT ^{[1
]}

Li, L ^{[1
]}

Cao, LZ ^{[1
]}

Chen, XH ^{[1
]}

机构：

[1] Univ Sci & Technol China, Dept Phys, Struct Res Lab, Hefei 230026, Anhui, Peoples R China

来源：

PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS | 2001年 / 363卷 / 04期

基金：

中国国家自然科学基金;

关键词：

MgB2; substitution effect; magnetic susceptibility; lattice parameters;

D O I：

10.1016/S0921-4534(01)01071-1

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

We report the alkali metal substitution effects on the structure and superconductivity of Mg(1-x)A(x)B(2) (A = Li and Na) compounds. X-ray diffraction results show that nearly single phase Mg(1-x)A(x)B(2) can be obtained for x less than or equal to 0.15 Li and x less than or equal to 0.2 Na substitution. The lattice parameters a and c decrease with Li substitution. As substituted by Na, both a and c show an increase at low Na concentration, then decrease with substitution at higher Na. concentrations. The change of a with Li and Na substitution is explained by two overlapping effects: ion size and an increase of in-plane coupling upon hole doping. The tendency of c-axis contraction in Mg1-xLixB2 is consistent with theoretical prediction. The T-c decreases when Li concentration is increased, while the change of T-c upon Na substitution is not apparent. (C) 2001 Elsevier Science B.V. All rights reserved.

引用

页码：219 / 223

页数：5