Isotope effect and the role of phonons in the iron-based superconductors

被引：15

作者：

Bang, Yunkyu ^{[1
,2
]}

机构：

[1] Chonnam Natl Univ, Dept Phys, Kwangju 500757, South Korea

[2] Asia Pacific Ctr Theoret Phys, Pohang 790784, South Korea

来源：

PHYSICAL REVIEW B | 2009年 / 79卷 / 09期

关键词：

antiferromagnetism; barium compounds; cerium compounds; electronic density of states; iron compounds; isotope effects; lanthanum compounds; neodymium compounds; phonons; potassium compounds; strontium compounds; superconducting materials; superconducting transition temperature; LAYERED SUPERCONDUCTOR; GAPS;

D O I：

10.1103/PhysRevB.79.092503

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We studied the isotope effect of phonon in the Fe-based superconductors using a phenomenological two band model for the sign-changing s-wave (+/- s-wave) state. Within this mean-field model, we showed that the large isotope effect is not inconsistent with the +/- s-wave pairing state and its high transition temperature. In principle, a large phonon isotope coefficient alpha implies a large phonon coupling constant. However, the asymmetric density of states between two bands substantially enhances the value of alpha, so that a moderate value of the phonon coupling constant (lambda(ph)approximate to 0.4) can produce a very large value of alpha(approximate to 0.4) as well as a high transition temperature together with an antiferromagnet-induced interaction.

引用

页数：4

共 34 条

[1]

BANG Y, ARXIV08080302

[2] Effects of phonon interaction on pairing in high-Tc superconductors [J].

Bang, Yunkyu .

PHYSICAL REVIEW B, 2008, 78 (07)

[3] Possible pairing states of the Fe-based superconductors [J].

Bang, Yunkyu ;

Choi, Han-Yong .

PHYSICAL REVIEW B, 2008, 78 (13)

[4]

BILL A, 2005, PHYS REV LETT, V95, DOI DOI 10.1103/PHYSREVLETT.95.257003

[5] Is LaFeAsO1-xFx an electron-phonon superconductor? [J].

Boeri, L. ;

Dolgov, O. V. ;

Golubov, A. A. .

PHYSICAL REVIEW LETTERS, 2008, 101 (02)

[6] Superconductivity at 41 K and its competition with spin-density-wave instability in layered CeO1-xFxFeAs [J].

Chen, G. F. ;

Li, Z. ;

Wu, D. ;

Li, G. ;

Hu, W. Z. ;

Dong, J. ;

Zheng, P. ;

Luo, J. L. ;

Wang, N. L. .

PHYSICAL REVIEW LETTERS, 2008, 100 (24)

[7] Robert Harry Kraichnan - Obituary [J].

Chen, Shiyi ;

Eyink, Gregory ;

Falkovich, Gregory ;

Frisch, Uriel ;

Orszag, Steven ;

Sreenivasan, Katepalli .

PHYSICS TODAY, 2008, 61 (05) :70-71

[8] Superconductivity at 43 K in SmFeAsO1-xFx [J].

Chen, X. H. ;

Wu, T. ;

Wu, G. ;

Liu, R. H. ;

Chen, H. ;

Fang, D. F. .

NATURE, 2008, 453 (7196) :761-762

[9] Unconventional superconductivity in Ba0.6K0.4Fe2As2 from inelastic neutron scattering [J].

Christianson, A. D. ;

Goremychkin, E. A. ;

Osborn, R. ;

Rosenkranz, S. ;

Lumsden, M. D. ;

Malliakas, C. D. ;

Todorov, I. S. ;

Claus, H. ;

Chung, D. Y. ;

Kanatzidis, M. G. ;

Bewley, R. I. ;

Guidi, T. .

NATURE, 2008, 456 (7224) :930-932

[10] Magnetism, superconductivity, and pairing symmetry in iron-based superconductors [J].

Chubukov, A. V. ;

Efremov, D. V. ;

Eremin, I. .

PHYSICAL REVIEW B, 2008, 78 (13)

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