【摘要】 报道了两种新型超导体MgB2 ,MgCNi3和氧化物高温超导体Bi2 Sr2 Ca0 9Ce0 1 Cu2 O8+y的热导率 温度关系和电阻率 温度关系 .实验发现氧化物高温超导体在进入超导态后热导有所上升 ,出现极大值后再下降 ,而MgB2 和MgCNi3则单调下降 .由Wiedemann Franz定律分别计算了它们在正常态的电子热导和声子热导 .由于共有化电子的非局域性 ,在MgB2 和MgCNi3中电子热导的贡献占据相当大的成分 .对电子热导的分析结果表明 ,在MgB2 和MgCNi3的电子热导中静态缺陷对电子的散射占主导地位 .更多还原

【Abstract】 The temperature dependence of thermal conductivity and electronic conductivity i n superconductor MgB 2, MgCNi 3 and Bi 2Sr 2Ca 0.9Ce 0.1Cu 2O 8+y are presented. The thermal conductivity of Bi 2Sr 2Ca 0.9Ce 0.1Cu 2O 8+y shows a peak under T c observed in cuprates, but those of MgB 2 and MgCNi 3 decrease monotonously. We calculate the electron thermal conductivity and the phonon thermal conductivity by Wiedem ann-Franz law. The electrons contribute a large fraction to the thermal conduc tivity in normal state of MgB 2 and MgCNi 3 because of the non-localigation o f mutual effect of electrons. The analysis on electronic thermal conductivity in dicates that the scattering by impurities prevails in electronic thermal resista nce of both samples.更多还原