隨著製成技術的進步，現今我們已踏入了奈米尺度的世界裡。在這奈米尺度的世界裡，令人著迷的是波粒二項性這種量子力學的現象。而另一項在量子世界中有趣的性質是自旋，粒子的一種自由度。控制這種電子的特性使我們製造出新的元件，例如：量子位元、自旋場效電晶體等等。

量子點可以把它視作一種人工的原子，為一固態量子元件。在量子點中，現在已經可以控制電子的數目。在量子點中如果有奇數顆電子，量子點可以視作一個磁性的雜質且被傳導電子包圍著，形成眾所皆知的近藤強關聯性電子態。然而，在一維的系統裡，如：量子線，也有發現近藤電子態相關的現象。本實驗由 N.J. Craig et al. 的想法出發—在鄰近兩個量子點之非局域性電子自旋操作的可能性。藉由控制其中之一的量子點中的電子數目，另一個量子點含奇數個電子會因為 Ruderman-Kittel-Kasuya-Yoshida (RKKY) 交互作用而產生變化。在本實驗中，我們把量子線和量子點排在鄰近的位置。在量子線中，我們觀察到零偏壓波峰值，而零偏壓波峰值為近藤關聯電子態的一個特徵。而後，藉由控制量子點中的電子數目去影響量子線中的電子自旋。連續性的零偏壓波峰值變化指出近藤關聯電子態在量子線中形成的可能性，而且 RKKY交互作用抑制了零邊壓波峰值的產生。我們的實驗結果指出更複雜的多量子點交互作
用系統，可以用量子線來取代其中一些操作。

Due to the improvement of the fabrication techniques, we enter a nanoscale world nowadays. The fascinating phenomenon in the nanoscale world is wave-particle duality, which is the main argument in the quantum mechanism. Another interesting property in
quantum world is spin as a degree of freedom of particles. Controlling this property of electrons allows us to manufacture new devices, like qubits-systems, field effect transistors based on spin.

Quantum dots are referred as an artificial atom, which are small solid-state devices. In a quantum dot, tuning the electron occupancy to be odd or even is capable now. With odd number of electrons, the dot now behaves as a magnetic impurity surrounded by the conduction electrons, forming the well-known Kondo correlation state [1,2]. However, it suggests that the Kondo correlation state may be formed in a quantum wire [4], a one
dimensional channel formed by split gates. Inspired by the idea proposed by N.J. Craig et al. [5], the non-local spin control is possible in the coupled quantum dots system. By controlling the number of electrons in one quantum dot, the other dot with an odd number of electrons will be changed due to the Ruderman-Kittel-Kasuya-Yoshida (RKKY) interaction. Here, we arrange the quantum wire close to the quantum dot. The zero-bias peaks, as a signature of a
Kondo singlet state, are observed in the quantum wire. Then, the number of electrons in the dot is manipulated to control the spin in the quantum wire. The continuous variations of zero-bias peaks show that the Kondo singlet state may be formed in the quantum wire, and the RKKY interaction causes the suppression of the zero-bias peak. The results suggest that the quantum wire could be used to entangle multiple quantum dots.

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