SiC and carbon nanotube distinctive effects on the superconducting properties of bulk MgB2

被引：57

作者：

Serrano, G. ^{[1
]}

Serquis, A. ^{[1
]}

Dou, S. X. ^{[2
]}

Soltanian, S. ^{[2
]}

Civale, L. ^{[3
]}

Maiorov, B. ^{[3
]}

Holesinger, T. G. ^{[3
]}

Balakirev, F. ^{[4
]}

Jaime, M. ^{[4
]}

机构：

[1] Ctr Atom Bariloche CONICET, Inst Balseiro, RA-8400 San Carlos De Bariloche, Rio Negro, Argentina

[2] Univ Wollongong, Inst Superconducting & Elect Mat, Wollongong, NSW 2522, Australia

[3] Los Alamos Natl Lab, Superconduct Technol Ctr, Los Alamos, NM 87545 USA

[4] Los Alamos Natl Lab, Natl High Magnet Field Lab, Los Alamos, NM 87545 USA

来源：

JOURNAL OF APPLIED PHYSICS | 2008年 / 103卷 / 02期

基金：

美国国家科学基金会; 澳大利亚研究理事会;

关键词：

D O I：

10.1063/1.2832463

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

This work describes in detail the simultaneous enhancement of the upper critical field (H-c2) and the critical current density (J(c)) of MgB2 bulk samples doped with nano-SiC particles, as well as single-walled and double-walled (dw) carbon nanotubes (CNTs). The magnetization properties were examined in a superconducting quantum interference device magnetometer, and four-probe transport measurements were performed using a 50 T pulsed magnet to determine H-c2(T). We found that the J(c) enhancement is similar in all doped samples at 5 K but nano-SiC addition is more effective to improve the flux pinning in the high temperature range (T >= 20 K); this improvement cannot solely be attributed to the C incorporation to the lattice but also to the presence of other types of defects (i.e., several kinds of nanoinclusions). CNTs produce a better C incorporation that is more effective to enhance H-c2 [i.e., dwCNT-doped samples reached a record H-c2(0)similar to 44 T value for bulk MgB2]. All the H-c2(T) curves obtained for different types of doping can be successfully described using a model for a two-gap superconductor in the dirty limit. (C) 2008 American Institute of Physics.

引用

页数：5

共 34 条

[1] Crystal chemistry of carbon-substituted MgB2 [J].