| 摘要: | 本研究致力於量子壓縮光源的生成及其光路的積體化，旨在提升光路的擴展性與操作穩定性。透過單通光參量放大器，我們成功產生了基於海森堡不確定性原理的非古典壓縮態光源，實現了在一個正交項上超越標準量子極限的最小擾動，同時其對應的另一個正交項擾動則略增，從而在量子感測領域中達到更高的精度。
在實現壓縮光源的過程中，本研究採用鈮酸鋰基板，並利用光束傳播法模擬波導的單模條件來優化轉換效率。透過一系列半導體製程技術，包括黃光微影、薄膜沉積、擴散、研磨拋光及蝕刻，我們製備了具有準相位匹配的周期性晶疇反轉結構和退火質子交換波導的晶片。進行古典量測後，結果顯示在1550nm波長下，晶片的傳播損耗為0.4414dB/cm，二倍頻轉換效率達到62.36%/W，相位匹配溫度為155.1℃，非線性增益的轉換效率和重疊係數分別為63.31%/W和0.4568。進一步地，通過在平衡零差檢測架構下對不同晶片進行測量，我們在泵浦功率為80mW、檢測效率為0.343的條件下，量測到0.760dB的反壓縮能級和-0.566dB的壓縮能級，從而驗證了量測架構的檢測能力。
未來研究將著重於優化質子交換波導的製程技術，結合反向質子交換製程來製作埋入式波導，以提升轉換效率和降低傳播損耗。此外，通過在鈮酸鋰基板中摻雜Mg、Zn離子來增加對光折變的抵抗能力，將使元件能夠在更高功率下運行。同時，埋入式波導的對稱模態分佈提高光纖耦合效率，將來能嘗試使用二次OPA放大過程來產生更大的壓縮能級，將為量子計算等應用提供更大的容錯。面向未來高度整合的光學晶片，使用具有更高光限制的鈮酸鋰薄膜將成為關鍵發展方向。
;This study is dedicated to the generation of quantum compressed light sources and the integration of their optical paths, aiming to enhance the scalability and operational stability of the optical routes. Through the use of a single-pass optical parametric amplifier, we successfully produced a non-classical compressed state light source based on the Heisenberg uncertainty principle, achieving minimal disturbance beyond the standard quantum limit on one orthogonal component, while slightly increasing the disturbance on its corresponding orthogonal component, thereby achieving higher precision in the quantum sensing domain.
In the process of realizing the compressed light source, this study employed a lithium niobate substrate and utilized the beam propagation method to simulate the single-mode conditions of the waveguide to optimize the conversion efficiency. Through a series of semiconductor fabrication techniques, including photolithography, thin-film deposition, diffusion, polishing, and etching, we prepared a chip with a quasi-phase-matched periodic domain inversion structure and annealed proton-exchanged waveguides. Subsequent classical measurements showed that at a wavelength of 1550nm, the chip′s propagation loss was 0.4414dB/cm, the frequency doubling conversion efficiency reached 62.36%/W, the phase-matching temperature was 155.1°C, and the conversion efficiency and overlap coefficient of the nonlinear gain were 63.31%/W and 0.4568, respectively. Furthermore, by measuring different chips under a balanced homodyne detection architecture, we measured a de-compression level of 0.760dB and a compression level of -0.566Db under the conditions of a pump power of 80mW and a detection efficiency of 0.343, thus verifying the measurement structure′s detection capability.
Future research will focus on optimizing the fabrication technology of proton-exchanged waveguides and combining the reverse-proton-exchange process to produce embedded waveguides to enhance the conversion efficiency and reduce propagation loss. Additionally, by doping the lithium niobate substrate with Mg and Zn ions to increase resistance to photorefractive effects, the components will be able to operate at higher power levels. At the same time, the symmetric mode distribution of embedded waveguides will improve the fiber coupling efficiency, and it may be possible to try using a secondary OPA amplification process to generate a larger compression level, providing greater fault tolerance for applications such as quantum computing. Looking forward to highly integrated optical chips in the future, the use of lithium niobate thin films with higher optical confinement will become a key direction for development. |
