近年來超導電路已經成為實行量子計算的方法中熱門的選擇之一，尤其因為其製程與控制都是基於已經成熟的技術，使得量子位元的參數具有可調性、容易擴增位元數，並且可以微波脈衝控制。另外，為了達到高精準度的量子計算，我們需要使用具有高同調性的量子位元(例如transmon 量子位元)，而三維的架構也能藉由降低基板的介電損耗來提升同調時間。
這篇論文將以重現參考文獻中[1]的微波激發相位邏輯閘為主軸。其中使用了兩個tranmson 量子位元，令它們和同一個空腔的基頻共振模耦合用以讀取狀態，而兩個量子位元的特定激發態能階則被調整至相近的能量，並以非共振的微波致使量子位元產生條件性的條件性的相位累積。同時這項實驗也將為實驗室未來的研究奠基，其中所有樣品的設計、製程和量測都是在台灣完成，而實驗內容也將幫助我們學習量子位元的參數調整以及微波控制。
實驗結果展示了我們製作量子位元樣品的能力，以及量測樣品參數的結果，而從實現微波激發相位閘的實驗我們也推斷出當參數調整得當時，可以得到只需要520奈秒操作時間的相位閘。最後，這項實驗中相關的知識和基礎將作為日後進行fluxonium位元微波控制邏輯閘的基石，幫助將來的研究發展。

Superconducting circuits is one of the most popular candidates for quantum computation in recent years. Based on matured fabrication and microwave technologies, the main advantages are engineerable qubit parameters, highly scalability, and the ability of controlling qubit states by fast microwave pulses. To achieve high-fidelity quantum computation, high coherence qubits (for example, transmon qubits) are required. Here we chose 3D cavity architecture to reduce dielectric loss on the interfaces to improve the coherence.
In this thesis we aimed to reproduce a microwave-activated phase (MAP) gate presented in Ref.[1]. Two 3D transmons are coupled to a single cavity mode for readout. Higher energy levels of the transmon are brought closed together such that an off-resonance drive induces a conditional phase accumulation. In this experiment all the design, fabrication, and measurement were done in Hsinchu, Taiwan. This experience helps us building up knowledge, experience and intuition of qubit design and microwave control.
Our result showed that we can fabricate and characterize the samples, as well as realize a microwave-activated conditional phase gate of a 520 ns gate time if the parameters are fine tuned. Besides, common knowledge involved in the experiment will be taken as a stepping stone for our future research on fluxonium two-qubit gates via microwave control.

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