Specific-heat evidence for strong electron correlations in the thermoelectric material (Na,Ca) Co2O4

被引：190

作者：

Ando, Y ^{[1
]}

Miyamoto, N

Segawa, K

Kawata, T

Terasaki, I

机构：

[1] Cent Res Inst Elect Power Ind, Komae, Tokyo 2018511, Japan

[2] Tokyo Univ Sci, Dept Phys, Shinjuku Ku, Tokyo 1628601, Japan

[3] Waseda Univ, Dept Appl Phys, Shinjuku Ku, Tokyo 1698555, Japan

来源：

PHYSICAL REVIEW B | 1999年 / 60卷 / 15期

关键词：

D O I：

10.1103/PhysRevB.60.10580

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The specific heat of (Na,Ca)Co2O4 is measured at low-temperatures to determine the magnitude of the electronic specific-heat coefficient gamma, in an attempt to gain an insight into the origin of the unusually large thermoelectric power of this compound. It is found that gamma is as large as similar to 48 mJ/molK(2), which is an order of magnitude larger than gamma of simple metals. This indicates that (Na,Ca)Ca2O4 is a strongly-correlated electron system, where the strong correlation probably comes from the low-dimensionality and the frustrated spin structure. We discuss how the large thermopower and its dependence on Ca doping can be understood with the strong electron correlations. [S0163-1829(99)01036-X].

引用

页码：10580 / 10583

页数：4

共 8 条

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