Superconducting characteristics in electron-doped layered hafnium nitride:: 15N isotope effect studies -: art. no. 100509

被引：45

作者：

Tou, H ^{[1
]}

Maniwa, Y

Yamanaka, S

机构：

[1] Hiroshima Univ, AdSM, Dept Quantum Matter, Higashihiroshima 7398530, Japan

[2] Tokyo Metropolitan Univ, Dept Phys, Hachioji, Tokyo 1920397, Japan

[3] Japan Sci & Technol Corp, CREST, Toshima Ku, Tokyo 1710031, Japan

[4] Hiroshima Univ, Grad Sch Engn, Dept Appl Chem, Higashihiroshima 7398527, Japan

来源：

PHYSICAL REVIEW B | 2003年 / 67卷 / 10期

关键词：

D O I：

10.1103/PhysRevB.67.100509

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We report N-15 nuclear magnetic resonance (NMR) and the nitrogen-isotope effect studies on c-axis oriented sample of Li-doped HfNCl with superconducting transition temperature T(c)similar to25.5 K. N-15 NMR Knight shift decreases toward zero below T-c, giving evidence that the pairing symmetry is an even-parity spin singlet, and that the nitrogen site plays an important role in the occurrence of superconductivity. A nitrogen isotope shift is found to be quite small, DeltaT(c)similar to0.1 K (alpha(N) = 0.07 +/- 0.02), which cannot reproduce such a high T-c within the traditional BCS framework.

引用

页数：4

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