二硼化鎂的超導臨界溫度相對高於其他常規超導，再加上分子結構相對於其他高溫超導體簡單許多，這有助於我們重新檢查常規超導的BCS理論與高溫超導之間的關聯。我們重新假定BCS理論的庫柏對是由單位晶胞裡的一對電子和裸聲子零點能交互作用形成，但這樣的模型並不如預期的形成庫柏對。接下來採用更接近庫珀的模型，改為討論一對電子和穿衣粒子的交互作用，其中穿衣粒子為包含離子聲波的準粒子。這個模型中，晶格震盪的零點能和離子電漿頻率之間的比例，會影響是否形成超導態。

The relatively high critical temperature and simple structure of MgB2 superconductor motivated the current study to revisit the BCS theory. The Cooper pair effect is reexamined by studying the interaction of an electron pair and a bare phonon of zero point energy (ZPE) in a unit cell. It is found that there is no Cooper pair effect in this theoretical model. The interaction of electron pair of dressed particle model that includes the ion sound wave and the electron screening is proposed that reveals similar effect as Cooper originally suggested. The effect of ZPE is to be included in this latter model and it suggests the importance of the ratio of ion plasma frequency and the lattice oscillation frequency of ZPE.

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