MgCxNi3是新發現的超導體，雖然它的Tc 8 K，比著名的MgB2小很多，因為它有很多另人困惑的物理性質使人感到有興趣。在這篇論文，我將提出MgCxNi3的比熱在不同磁場下的結果，與壓力效應的量測。這些實驗可以清楚的解釋MgCNi3的電子與聲子的交互作用與超導電性，和因為磁性因素需做一些小量的修正。由比熱量測所得之參數顯示MgCxNi3為BCS常見的s-wave超導體。壓力效應的數據dTc/dP是正值，與Kumary et al.所得結果相異，因此留下空間以讓人進一步去確立與改善帶狀結構的計算。

The newly discovered superconductivity in MgCNi3, though with Tc£8 K lower than that of the celebrated MgB2, is probably even more interesting in its many puzzling physical properties. In this article, we report the results of C(T) experiments, and the pressure effects on MgCNi3. These experimental evidences clearly demonstrate that superconductivity in MgCNi3 is well explained within the conventional electron-phonon interaction scenario, at most with minor modifications from the magnetic interaction. The thermodynamic data C(T) is consistent with the conventional s-wave order parameter. Surprisingly, the pressure effects data dTc/dP is positive which leaves room for further improvements in the band structure calculations.

目 次
中文摘要
英文摘要
誌謝
目次
表目錄
圖目錄

第一章 簡介
(一)超導體簡介……………………………………………………..1
(二)MgCxNi3簡介…………………………………………………...3

第二章 理論
(一)超導體的基本特性及現象…………………………………….6
(二)超導體的電動力學……………………………………………..7
(三)超導體的微觀理論……………………………………………..9
(四)基本比熱理論…………………………………………………11

第三章 實驗方法
(一)樣品製作………………………………………………………17
(二)結構檢測………………………………………………………17
(三)低溫比熱………………………………………………………19
(四)高壓效應………………………………………………………31
第四章 測量結果與分析
(一)結構檢測………………………………………………………35
(二)電性量測………………………………………………………37
(三)比熱量測………………………………………………………41
(四)高壓效應………………………………………………………52
第五章 結論
(一)根據比熱所得…………………………………………………60
(二)根據高壓效應…………………………………………………61

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