Enhancement of Pairing Interaction and Magnetic Fluctuations toward a Band Insulator in an Electron-Doped LixZrNCl Superconductor

被引：50

作者：

Kasahara, Yuichi ^{[1
]}

Kishiume, Tsukasa ^{[1
]}

Takano, Takumi ^{[1
]}

Kobayashi, Katsuki ^{[1
]}

Matsuoka, Eiichi ^{[2
]}

Onodera, Hideya ^{[2
]}

Kuroki, Kazuhiko ^{[3
]}

Taguchi, Yasujiro ^{[4
]}

Iwasa, Yoshihiro ^{[1
,5
]}

机构：

[1] Tohoku Univ, Inst Mat Res, Sendai, Miyagi 9808577, Japan

[2] Tohoku Univ, Dept Phys, Sendai, Miyagi 9808578, Japan

[3] Univ Electrocommun, Dept Appl Phys & Chem, Tokyo 1828585, Japan

[4] RIKEN, ASI, CMRG, Wako, Saitama 3510198, Japan

[5] Japan Sci & Technol Corp, CREST, Kawaguchi, Saitama 3320012, Japan

来源：

PHYSICAL REVIEW LETTERS | 2009年 / 103卷 / 07期

关键词：

NITRIDE CHLORIDE; HAFNIUM NITRIDE; ZIRCONIUM; SYSTEMS; STATE; HEAT;

D O I：

10.1103/PhysRevLett.103.077004

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

The doping dependence of specific heat and magnetic susceptibility has been investigated for LixZrNCl superconductors derived from a band insulator. As the carrier concentration is decreased, the anisotropy of superconducting gap changes from highly anisotropic to almost isotropic. It was also found that, upon reducing carrier density, the superconducting coupling strength and the magnetic susceptibility are concomitantly enhanced in parallel with T-c, while the density of states at the Fermi level is kept almost constant. Theoretical calculations taking into account the on-site Coulomb interaction reproduced the experimental results, suggesting a possible pairing mediated by magnetic fluctuations, even in the doped band insulators.

引用

页数：4

共 32 条

[1] THE RESONATING VALENCE BOND STATE IN LA2CUO4 AND SUPERCONDUCTIVITY [J].

ANDERSON, PW .

SCIENCE, 1987, 235 (4793) :1196-1198

[2] Resonating valence bond mechanism of impurity band superconductivity in diamond [J].

Baskaran, G. .

JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM, 2008, 21 (01) :45-49

[3] POSSIBLE HIGH-TC SUPERCONDUCTIVITY IN THE BA-LA-CU-O SYSTEM [J].

BEDNORZ, JG ;

MULLER, KA .

ZEITSCHRIFT FUR PHYSIK B-CONDENSED MATTER, 1986, 64 (02) :189-193

[4] CONSERVING APPROXIMATIONS FOR STRONGLY CORRELATED ELECTRON-SYSTEMS - BETHE-SALPETER-EQUATION AND DYNAMICS FOR THE TWO-DIMENSIONAL HUBBARD-MODEL [J].

BICKERS, NE ;

SCALAPINO, DJ ;

WHITE, SR .

PHYSICAL REVIEW LETTERS, 1989, 62 (08) :961-964

[5] Electronic collective modes and superconductivity in layered conductors [J].

Bill, A ;

Morawitz, H ;

Kresin, VZ .

PHYSICAL REVIEW B, 2003, 68 (14)

[6] 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)

[7] Magnetic order close to superconductivity in the iron-based layered LaO1-xFxFeAs systems [J].

de la Cruz, Clarina ;

Huang, Q. ;

Lynn, J. W. ;

Li, Jiying ;

Ratcliff, W., II ;

Zarestky, J. L. ;

Mook, H. A. ;

Chen, G. F. ;

Luo, J. L. ;

Wang, N. L. ;

Dai, Pengcheng .

NATURE, 2008, 453 (7197) :899-902

[8]

*EPAPS, EPRLTAO103030935 EPA

[9] Electronic structures and instabilities of ZrNCl and HfNCl: implications for superconductivity in the doped compounds [J].

Felser, C ;

Seshadri, R .

JOURNAL OF MATERIALS CHEMISTRY, 1999, 9 (02) :459-464

[10] Electronic structure of superconducting layered zirconium and hafnium nitride [J].

Hase, I ;

Nishihara, Y .

PHYSICAL REVIEW B, 1999, 60 (03) :1573-1581

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