近年來，由於量子科學相關研究的快速突破，新世代量子計算及加密通訊在這個時代即將變成可能，然而現今的量子系統多半建立於超導量子位元，其嚴苛的溫度要求、龐大的系統體積以及昂貴的造價仍然嚴重地限制了它的應用潛力。但是以單光子源作為媒介的量子系統卻不受到此限制，不但能夠操作於室溫，並且能夠直接整合於目前成熟的矽光子元件和光纖通訊網路，讓積體量子光路晶片成為可能。

本研究旨在開發高製程容忍度的積體化鈮酸鋰單光子晶片，包含準相位匹配結構、寬頻波導偏振分光器以及波長濾波器。透過絕熱耦合理論的計算，本研究縮短了以往絕熱偏振分光器的元件長度，同時保留其高製程容忍度以及寬頻運作的特性，並成功地將單光子源整合於同一晶片上。

In recent years, the explosively growing field of quantum information science has driven a dramatic surge of research into developing single photon sources with high brightness, robustness and scalability. In this work, we have experimentally demonstrated the first fully-integrated heralded single photon source using ti-diffused periodically poled lithiun niobate (PPLN) waveguides. A novel design of ultra-broadband, highly fabrication tolerant PBS and pump filter based on spatial adiabatic passage is proposed. The measured PERs for TE and TM polarizations are greater than 15 dB over a wavelength range of 140 nm and 100 nm, respectively, even in the presence of near 1 µm width deviation. Due to the background noise caused by free space coupling and scattering, the highest PERs are limited to near 15 dB level, which will be further improved by endfacet fiber pigtailing.

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