Two-Gap Superconductivity in Ba1-xKxFe2As2: A Complementary Study of the Magnetic Penetration Depth by Muon-Spin Rotation and Angle-Resolved Photoemission

被引：107

作者：

Khasanov, R. ^{[1
]}

Evtushinsky, D. V. ^{[2
]}

Amato, A. ^{[1
]}

Klauss, H. -H. ^{[3
]}

Luetkens, H. ^{[1
]}

Niedermayer, Ch. ^{[4
,5
]}

Buechner, B. ^{[2
]}

Sun, G. L. ^{[6
]}

Lin, C. T. ^{[6
]}

Park, J. T. ^{[6
]}

Inosov, D. S. ^{[6
]}

Hinkov, V. ^{[6
]}

机构：

[1] Paul Scherrer Inst, Lab Muon Spin Spect, CH-5232 Villigen, Switzerland

[2] IFW Dresden, Inst Solid State Res, D-01171 Dresden, Germany

[3] Tech Univ Dresden, IFP, D-01069 Dresden, Germany

[4] Paul Scherrer Inst, Neutron Scattering Lab, CH-5232 Villigen, Switzerland

[5] Swiss Fed Inst Technol, CH-5232 Villigen, Switzerland

[6] Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany

来源：

PHYSICAL REVIEW LETTERS | 2009年 / 102卷 / 18期

关键词：

GAPS;

D O I：

10.1103/PhysRevLett.102.187005

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We investigate the magnetic penetration depth lambda in superconducting Ba1-xKxFe2As2 (T-c similar or equal to 32 K) with muon-spin rotation (mu SR) and angle-resolved photoemission (ARPES). Using mu SR, we find the penetration-depth anisotropy gamma(lambda)=lambda(c)/lambda(ab) and the second-critical-field anisotropy gamma(Hc2) to show an opposite T evolution below T-c. This dichotomy resembles the situation in the two-gap superconductor MgB2. A two-gap scenario is also suggested by an inflection point in the in-plane penetration depth lambda(ab) around 7 K. The complementarity of mu SR and ARPES allows us to pinpoint the values of the two gaps and to arrive to a remarkable agreement between the two techniques concerning the full T evolution of lambda(ab). This provides further support for the described scenario and establishes ARPES as a tool to assess macroscopic properties of the superconducting condensate.

引用

页数：4

共 29 条

[1] Muon-spin-relaxation studies of magnetic order and superfluid density in antiferromagnetic NdFeAsO, BaFe2As2, and superconducting Ba1-xKxFe2As2 [J].

Aczel, A. A. ;

Baggio-Saitovitch, E. ;

Budko, S. L. ;

Canfield, P. C. ;

Carlo, J. P. ;

Chen, G. F. ;

Dai, Pengcheng ;

Goko, T. ;

Hu, W. Z. ;

Luke, G. M. ;

Luo, J. L. ;

Ni, N. ;

Sanchez-Candela, D. R. ;

Tafti, F. F. ;

Wang, N. L. ;

Williams, T. J. ;

Yu, W. ;

Uemura, Y. J. .

PHYSICAL REVIEW B, 2008, 78 (21)

[2] Determination of anisotropic Hc2 up to 60 T in Ba0.55K0.45Fe2As2 single crystals [J].

Altarawneh, M. M. ;

Collar, K. ;

Mielke, C. H. ;

Ni, N. ;

Bud'ko, S. L. ;

Canfield, P. C. .

PHYSICAL REVIEW B, 2008, 78 (22)

[3]

ANGST M, 2004, FOCUS SUPERCONDUCTIV, P1

[4] FLUX DISTRIBUTION AND PENETRATION DEPTH MEASURED BY MUON SPIN ROTATION IN HIGH-TC SUPERCONDUCTORS [J].

BRANDT, EH .

PHYSICAL REVIEW B, 1988, 37 (04) :2349-2352

[5] Proximity of antiferromagnetism and superconductivity in LaFeAsO1-xFx:: Effective Hamiltonian from ab initio studies [J].

Cao, Chao ;

Hirschfeld, P. J. ;

Cheng, Hai-Ping .

PHYSICAL REVIEW B, 2008, 77 (22)

[6]

CHANDRASEKHAR BS, 1993, ANN PHYS-LEIPZIG, V2, P535, DOI 10.1002/andp.19935050604

[7] Observation of Fermi-surface-dependent nodeless superconducting gaps in Ba0.6K0.4Fe2As2 [J].

Ding, H. ;

Richard, P. ;

Nakayama, K. ;

Sugawara, K. ;

Arakane, T. ;

Sekiba, Y. ;

Takayama, A. ;

Souma, S. ;

Sato, T. ;

Takahashi, T. ;

Wang, Z. ;

Dai, X. ;

Fang, Z. ;

Chen, G. F. ;

Luo, J. L. ;

Wang, N. L. .

EPL, 2008, 83 (04)

[8] Momentum dependence of the superconducting gap in Ba1-xKxFe2As2 [J].

Evtushinsky, D. V. ;

Inosov, D. S. ;

Zabolotnyy, V. B. ;

Koitzsch, A. ;

Knupfer, M. ;

Buechner, B. ;

Viazovska, M. S. ;

Sun, G. L. ;

Hinkov, V. ;

Boris, A. V. ;

Lin, C. T. ;

Keimer, B. ;

Varykhalov, A. ;

Kordyuk, A. A. ;

Borisenko, S. V. .

PHYSICAL REVIEW B, 2009, 79 (05)

[9]

EVTUSHINSKY DV, ARXIV09034362

[10]

GOKO T, ARXIV08081425

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