A Sharp Peak of the Zero-Temperature Penetration Depth at Optimal Composition in BaFe2(As1-xPx)2

被引：270

作者：

Hashimoto, K. ^{[1
]}

Cho, K. ^{[2
,3
]}

Shibauchi, T. ^{[1
]}

Kasahara, S. ^{[1
,4
]}

Mizukami, Y. ^{[1
]}

Katsumata, R. ^{[1
]}

Tsuruhara, Y. ^{[1
]}

Terashima, T. ^{[4
]}

Ikeda, H. ^{[1
]}

Tanatar, M. A. ^{[2
]}

Kitano, H. ^{[5
]}

Salovich, N. ^{[6
]}

Giannetta, R. W. ^{[6
]}

Walmsley, P. ^{[7
]}

Carrington, A. ^{[7
]}

Prozorov, R. ^{[2
,3
]}

Matsuda, Y. ^{[1
]}

机构：

[1] Kyoto Univ, Dept Phys, Kyoto 6068502, Japan

[2] Ames Lab, Ames, IA USA

[3] Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA

[4] Kyoto Univ, Res Ctr Low Temp & Mat Sci, Kyoto 6068501, Japan

[5] Aoyama Gakuin Univ, Dept Math & Phys, Chuo Ku, Sagamihara, Kanagawa 2525258, Japan

[6] Univ Illinois, Loomis Lab Phys, Urbana, IL 61801 USA

[7] Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England

来源：

SCIENCE | 2012年 / 336卷 / 6088期

基金：

日本学术振兴会; 英国工程与自然科学研究理事会;

关键词：

SUPERCONDUCTIVITY; CROSSOVER; BCS;

D O I：

10.1126/science.1219821

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

In a superconductor, the ratio of the carrier density, n, to its effective mass, m*, is a fundamental property directly reflecting the length scale of the superfluid flow, the London penetration depth, lambda(L). In two-dimensional systems, this ratio n/m* (similar to 1/lambda(2)(L)) determines the effective Fermi temperature, T-F. We report a sharp peak in the x-dependence of lambda(L) at zero temperature in clean samples of BaFe2(As1-xPx)(2) at the optimum composition x = 0.30, where the superconducting transition temperature T-c reaches a maximum of 30 kelvin. This structure may arise from quantum fluctuations associated with a quantum critical point. The ratio of T-c/T-F at x = 0.30 is enhanced, implying a possible crossover toward the Bose-Einstein condensate limit driven by quantum criticality.

引用

页码：1554 / 1557

页数：4

共 29 条

[1] What lies beneath the dome? [J].