當電晶體的尺寸難以再進一步縮小的時後，在現今後摩爾時代介觀物理被視為一個下一個世代的關鍵領域，因此，很多關於介觀物理的現象是很值得被系統性地研究。舉例而言，近藤效應已經在帶有磁性雜質的金屬當中或是束縛奇數顆電子的量子點之中被廣泛地研究，然而，一個類似近藤效應的現象，換言之，在電導中所出現的零點偏壓反常峰值，已經可以在量子線當中被觀察到，而量子線通常被視為是一個開放系統且不應該存在近藤效應。
在這篇論文裡，我們設計了一個量子點和量子線的耦合系統，然後藉此研究在量子線中是否存在束縛態。接著，藉由研究溫度、磁場或操作佔據在量子點附近的電子對於零點偏壓反常峰值的改變，得到的實驗結果顯示量子線的傳輸特性可以被調節，指出在量子線中有近藤效應的量子態之存在，因此，這個實驗結果可以幫助我們在介觀物理中更加瞭解這個重要的議題。

Mesoscopic physics is regarded as a key field for next generation devices in post-Moore era today, where the transistor size is difficult to be further scaled down. Therefore, lots of phenomenon with respect to mesoscopic physics is worth to be investigated systematically. For instance, the Kondo effect has been widely studied in a metal with magnetic impurities or in a quantum dot (QD) confining odd number of electrons. However, Kondo-like phenomenon, i.e., the appearance of zero-bias anomaly (ZBA) peak in the conductance, has also been observed in a quantum point contact (QPC), which is generally considered as an open system and shall not host the Kondo effect.
In this thesis, we design a QD-QPC couple device and then study whether the bound states exist in the QPC. By studying the variation of ZBA in QPC with temperature, magnetic field, and the manipulation of the electron occupancy of nearby QD, the experiment result shows that the transport properties of QPC can be modulated, indicating the existence of Kondo state in the QPC. In this thesis, we have a better understanding of this important problem in mesoscopic physics.

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