中国物理B ›› 2002, Vol. 11 ›› Issue (3): 282-287.doi: 10.1088/1009-1963/11/3/316

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Study on the in-plane electrical resistivity and thermoelectric power in single crystals of La2-xBaxCuO4

李鹏程, 杨宏顺, 李志权, 柴一晟, 曹烈兆   

  1. Structure Research Laboratory, Department of Physics, University of Science and Technology of China, Hefei 230026, China
  • 收稿日期:2001-09-12 修回日期:2001-10-29 出版日期:2002-03-13 发布日期:2005-06-13
  • 基金资助:
    Project supported by the Major State Basic Research Development Programme of China (Grant No 19990646).

Study on the in-plane electrical resistivity and thermoelectric power in single crystals of La2-xBaxCuO4

Li Peng-Cheng (李鹏程), Yang Hong-Shun (杨宏顺), Li Zhi-Quan (李志权), Chai Yi-Sheng (柴一晟), Cao Lie-Zhao (曹烈兆)   

  1. Structure Research Laboratory, Department of Physics, University of Science and Technology of China, Hefei 230026, China
  • Received:2001-09-12 Revised:2001-10-29 Online:2002-03-13 Published:2005-06-13
  • Supported by:
    Project supported by the Major State Basic Research Development Programme of China (Grant No 19990646).

摘要: The in-plane electrical resistivity and thermoelectric power have been measured on single crystals of La2-xBaxCuO4 at around x=0.125. The room temperature resistivity and thermopower have their maximum values at x=0.125, indicating that the carrier concentration is the minimum and the carriers are most strongly localized at x=0.125. The observed semiconductor-like behaviour can be well described by the weak-localized quasi-two-dimensional state. The steep rise in electric resistivity of the sample at x=0.125 below 70K is attributed to the formation of static stripe-order of holes and spins, which are pinned by the low-temperature tetragonal (LTT) structure, as discovered in La1.48Nd0.4Sr0.12CuO4. The temperature dependence of electric resistivity below 70K is still well described by the formula ρ∝ lnT. A definite change in the slope of thermopower is observed at the low-temperature orthorhombic-LTT structural phase transition temperature. The origin of the 1/8 anomaly is discussed in the text.

Abstract: The in-plane electrical resistivity and thermoelectric power have been measured on single crystals of La2-xBaxCuO4 at around x=0.125. The room temperature resistivity and thermopower have their maximum values at x=0.125, indicating that the carrier concentration is the minimum and the carriers are most strongly localized at x=0.125. The observed semiconductor-like behaviour can be well described by the weak-localized quasi-two-dimensional state. The steep rise in electric resistivity of the sample at x=0.125 below 70K is attributed to the formation of static stripe-order of holes and spins, which are pinned by the low-temperature tetragonal (LTT) structure, as discovered in La1.48Nd0.4Sr0.12CuO4. The temperature dependence of electric resistivity below 70K is still well described by the formula $\rho \varpropto \ln T$. A definite change in the slope of thermopower is observed at the low-temperature orthorhombic-LTT structural phase transition temperature. The origin of the 1/8 anomaly is discussed in the text.

Key words: resistivity, thermopower

中图分类号:  (Charge carriers: generation, recombination, lifetime, and trapping)

  • 72.20.Jv
72.20.Pa (Thermoelectric and thermomagnetic effects) 72.15.Rn (Localization effects (Anderson or weak localization))