由於製程技術的先進發展，人們得以實現低維度系統的量子元件，並藉此進入到量子力學的世界。在低維度的量子元件中，我們可以觀測到量子化的電導平台，並能進一步去研究由於電子與電子交互作用產生的各種多體效應。
自旋作為電子的其中一項自由度，能夠攜帶資訊並因此發展出了量子傳輸元件的新領域。如今，人們可以把電子限制在一個非常小的空間裡並精確的操控電子的自旋。像這樣被限制在局部的電子，是自旋量子計算的基礎，也已經在量子點元件中被密集的研究過。令人驚訝的是，在最近的研究中發現了量子線裡有近似近藤效應的行為，這暗指了在開放系統中可能存在著被束縛的自旋態。然而，這樣的束縛態能否存在於一維通道中仍然無法定論。
在這篇論文裡，描述了一系列用來探測量子線中束縛電子態的實驗。我們的元件主要由兩層不同的閘設計所組成，下層為標準的量子點接觸，讓我們可以用電位限制的方式來製造出一維的通道，而上層則是用來產生類似於量子點的額外電位限制，目的是用來控制量子線中與自旋相關的現象。藉由觀察到庫倫阻塞效應與零偏壓異常現象，我們獲得了量子線中確實存在著束縛電子態的證據。此外，我們也發現與近藤效應相關的行為以及0.25平台皆會被額外產生的電子限制所影響。我們的結果給予了實驗上研究開放系統中束縛電子態的一個可能性，並且提供了可行的方法來實現自旋量子電腦。

Thanks to the advances of the fabrication techniques, the realization of quantum devices in low-dimensional system led us into the world of quantum mechanics. In low-dimensional quantum devices, we can observe quantized conductance plateaus and further study various many-body effects driven by electron-electron interactions.
Spin, as a degree of freedom of electrons, is capable of carrying information and thus develops a new area for devices in quantum transport. Nowadays, people are able to confine electrons within a small space to precisely manipulate the spin of the electrons. Such a localized spin is the basis of spin-based quantum computing and has been intensively investigated in quantum dot devices. Surprisingly, recent researches have found Kondo-like behavior in quantum wires, implying the possibility of bound spins forming in the open systems. However, whether bound states can exist in a one-dimensional channel is still debated.
This thesis describes a series of experiments which explore the electrons transport through a bound spin within a quantum wire. Our device consists of two different gate designs lying in two layers separated by an oxide. The lower layer is a standard quantum point contact, which can potentially define a one-dimensional channel, while the upper layer is responsible for the dot-like confinement to control the spin-related phenomena of the one-dimensional electron transport. We obtain evidences of the existence of bound spins in a quantum wire by observing Coulomb blockade peaks and the zero bias anomaly. Also, the Kondo-like behavior and 0.25 plateaus are both affected by introducing the extra confinement. Our results provide a possible way for the experimental studies of the bound spins in the open systems and offer a feasible platform for spin-based quantum computers.

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