Doping evolution of superconducting gaps and electronic densities of states in Ba(Fe1-xCox)2As2 iron pnictides

被引：111

作者：

Hardy, F. ^{[1
]}

Burger, P. ^{[1
]}

Wolf, T. ^{[1
]}

Fisher, R. A. ^{[3
]}

Schweiss, P. ^{[1
]}

Adelmann, P. ^{[1
]}

Heid, R. ^{[1
]}

Fromknecht, R. ^{[1
]}

Eder, R. ^{[1
]}

Ernst, D. ^{[1
]}

v. Loehneysen, H. ^{[1
,2
]}

Meingast, C. ^{[1
]}

机构：

[1] Karlsruher Inst Technol, Inst Festkorperphys, D-76021 Karlsruhe, Germany

[2] Karlsruher Inst Technol, Inst Phys, D-76128 Karlsruhe, Germany

[3] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA

来源：

EPL | 2010年 / 91卷 / 04期

关键词：

D O I：

10.1209/0295-5075/91/47008

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

An extensive calorimetric study of the normal- and superconducting-state properties of Ba(Fe1-xCox)(2)As-2 is presented for 0 < x < 0.2. The normal- state Sommerfeld coefficient increases (decreases) with Co doping for x < 0.06 (x > 0.06), which illustrates the strong competition between magnetism and superconductivity to monopolize the Fermi surface in the underdoped region and the filling of the hole bands for overdoped Ba(Fe(1-x)Cox)(2)As-2. All superconducting samples exhibit a residual electronic density of states of unknown origin in the zero-temperature limit, which is minimal at optimal doping but increases to the normal- state value in the strongly under- and over-doped regions. The remaining specific heat in the superconducting state is well described using a two-band model with isotropic s-wave superconducting gaps.

引用

页数：6

共 52 条

[1] Spectroscopic and thermodynamic properties in a four-band model for pnictides [J].

Benfatto, L. ;

Cappelluti, E. ;

Castellani, C. .

PHYSICAL REVIEW B, 2009, 80 (21)

[2] Specific heat of single crystal MgB2:: A two-band superconductor with two different anisotropies -: art. no. 257001 [J].

Bouquet, F ;

Wang, Y ;

Sheikin, I ;

Plackowski, T ;

Junod, A ;

Lee, S ;

Tajima, S .

PHYSICAL REVIEW LETTERS, 2002, 89 (25)

[3] Phenomenological two-gap model for the specific heat of MgB [J].

Bouquet, F ;

Wang, Y ;

Fisher, RA ;

Hinks, DG ;

Jorgensen, JD ;

Junod, A ;

Phillips, NE .

EUROPHYSICS LETTERS, 2001, 56 (06) :856-862

[4] Specific heat of Mg11B2:: Evidence for a second energy cap -: art. no. 047001 [J].

Bouquet, F ;

Fisher, RA ;

Phillips, NE ;

Hinks, DG ;

Jorgensen, JD .

PHYSICAL REVIEW LETTERS, 2001, 87 (04) :47001-1

[5] Jump in specific heat at the superconducting transition temperature in Ba(Fe1-xCox)2As2 and Ba(Fe1-xNix)2As2 single crystals [J].

Bud'ko, Sergey L. ;

Ni, Ni ;

Canfield, Paul C. .

PHYSICAL REVIEW B, 2009, 79 (22)

[6] Decoupling of the superconducting and magnetic/structural phase transitions in electron-doped BaFe2As2 [J].

Canfield, P. C. ;

Bud'ko, S. L. ;

Ni, Ni ;

Yan, J. Q. ;

Kracher, A. .

PHYSICAL REVIEW B, 2009, 80 (06)

[7] Determination of the phase diagram of the electron-doped superconductor Ba(Fe1-xCox)2As2 [J].

Chu, Jiun-Haw ;

Analytis, James G. ;

Kucharczyk, Chris ;

Fisher, Ian R. .

PHYSICAL REVIEW B, 2009, 79 (01)

[8] Effects of Al and C doping on the electronic structure and phonon renormalization in MgB2 [J].

De la Pena-Seaman, O. ;

de Coss, R. ;

Heid, R. ;

Bohnen, K. -P. .

PHYSICAL REVIEW B, 2009, 79 (13)

[9] 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)

[10] Interband superconductivity: Contrasts between Bardeen-Cooper-Schrieffer and Eliashberg theories [J].

Dolgov, Oleg V. ;

Mazin, Igor I. ;

Parker, David ;

Golubov, Alexander A. .

PHYSICAL REVIEW B, 2009, 79 (06)

← 1 2 3 4 5 6 →