Specific heat of MgB2 after irradiation

被引：63

作者：

Wang, YX

Bouquet, F

Sheikin, I

Toulemonde, P

Revaz, B

Eisterer, M

Weber, HW

Hinderer, J

Junod, A

机构：

[1] Univ Geneva, Dept Phys Mat Condensee, CH-1211 Geneva 4, Switzerland

[2] Univ Vienna, Atominst, A-1020 Vienna, Austria

[3] GHMFL, Max Planck Inst, F-38042 Grenoble, France

来源：

JOURNAL OF PHYSICS-CONDENSED MATTER | 2003年 / 15卷 / 06期

关键词：

D O I：

10.1088/0953-8984/15/6/315

中图分类号：

O469 [凝聚态物理学];

学科分类号：

070205 ;

摘要：

We studied the effect of disorder on the superconducting properties of polycrystalline MgB2 by specific-heat measurements. In the pristine state, these measurements give a bulk confirmation of the presence of two superconducting gaps with 2Delta(0)/k(B)T(c) = 1.3 and 3.9 with nearly equal weights. The scattering introduced by irradiation suppresses T-c and tends to average the two gaps although less than predicted by theory. We also found that by a suitable irradiation process by fast neutrons, a substantial bulk increase of dH(c2)/dT at T-c can be obtained without sacrificing more than a few degrees in T-c. The upper critical field of the sample after irradiation exceeds 28 T at T --> 0.

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页码：883 / 893

页数：11

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