Two-band superconductivity in LaFeAsO0.89F0.11 at very high magnetic fields

被引：483

作者：

Hunte, F. ^{[1
]}

Jaroszynski, J. ^{[1
]}

Gurevich, A. ^{[1
]}

Larbalestier, D. C. ^{[1
]}

Jin, R. ^{[2
]}

Sefat, A. S. ^{[2
]}

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

Sales, B. C. ^{[2
]}

Christen, D. K. ^{[2
]}

Mandrus, D. ^{[2
]}

机构：

[1] Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32310 USA

[2] Oak Ridge Natl Lab, Mat Sci & Technol Div, Oak Ridge, TN 37831 USA

来源：

NATURE | 2008年 / 453卷 / 7197期

基金：

美国国家科学基金会;

关键词：

D O I：

10.1038/nature07058

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：

The recent synthesis of the superconductor LaFeAsO0.89F0.11 with transition temperature T-c approximate to 26 K ( refs 1 - 4) has been quickly followed by reports of even higher transition temperatures in related compounds: 41 K in CeFeAsO0.84F0.16 ( ref. 5), 43 K in SmFeAsO0.9F0.1 ( ref. 6), and 52 K in NdFeAsO0.89F0.11 and PrFeAsO0.89F0.11 ( refs 7, 8). These discoveries have generated much interest(9,10) in the mechanisms and manifestations of unconventional superconductivity in the family of doped quaternary layered oxypnictides LnOTMPn ( Ln: La, Pr, Ce, Sm; TM: Mn, Fe, Co, Ni; Pn: P, As), because many features of these materials set them apart from other known superconductors. Here we report resistance measurements of LaFeAsO0.89F0.11 at high magnetic fields, up to 45 T, that show a remarkable enhancement of the upper critical field B-c2 compared to values expected from the slopes dB(c2)/ dT approximate to 2 T K-1 near Tc, particularly at low temperatures where the deduced B-c2(0) approximate to 63 - 65 T exceeds the paramagnetic limit. We argue that oxypnictides represent a new class of high-field superconductors with B-c2 values surpassing those of Nb3Sn, MgB2 and the Chevrel phases, and perhaps exceeding the 100 T magnetic field benchmark of the high- T-c copper oxides.

引用

页码：903 / 905

页数：3

共 26 条

[1]

AHILAN K, 2008, 19F NMR INVESTIGATIO

[2]

BLATTER G, 2003, PHYS SUPERCONDUCTORS, V1, P800

[3]

CAO C, 2008, COEXISTENCE ANTIFERR

[4]

CHEN GF, 2008, SUPERCONDUCTING PROP

[5]

CHEN GF, 2008, SUPERCONDUCTIVITY 41

[6]

CHEN XH, 2008, SUPERCONDUCTIVITY 43

[7]

DAI X, 2008, EVEN PARITY ORBITAL

[8]

DONG J, 2008, COMPETING ORDERS SPI

[9]

Glazman L. I., 1988, Soviet Physics - JETP, V67, P1235

[10] Limits of the upper critical field in dirty two-gap superconductors [J].

Gurevich, A. .

PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS, 2007, 456 (1-2) :160-169

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