基于量子频率转换和半导体量子点的高效可调谐触发式单光子源

Single-photon source is one of the key elements in quantum science and technology. Due to its excellent optical properties and compatibility with semiconductor process technology, self-assembled quantum dots are widely regarded as one of the most promising candidates for solid-state single-photon emitters. However, accurate controlling of the emission wavelength is still a challenge because of the random nature of the self-assemble process in the quantum dot growth. In this proposal, we are going to focus on (1) epitaxial growth of GaAs/AlGaAs quantum dots (2) realization of AlGaAs_On_Insulator chip structure for quantum frequency conversion (3) design and fabrication of nanophotonic devices for on-chip frequency conversion and (4) characterizations of single-photon generation and frequency conversion. This project is aiming at investigating the physical mechanisms of quantum noises in the frequency conversion process, developing the fabrication process for hybrid quantum photonic chips and experimental demonstrating high-performance single-photon generation and frequency conversion processes on the same chip. This project will provide the quantum light source for on-chip quantum information process, e.g., quantum waking and Boson sampling etc.

单光子源是量子科学与信息技术中最核心的组成部分之一。由于优良的光学特性和与现代半导体工体工艺的兼容性，自组织量子已经被公认为当今最好的固态单光子发射源之一。然而，由于量子点自组织生长过程中的内随机属性，半导体量子点的发光波长依然难以精确控制。因此实现宽带可调量子点单光子源显得尤为紧迫。本项目拟开展 （1）高质量GaAs/AlGaAs量子点外延生长（2）制备用于单光子量子频率转换的AlGaAs_on_Insulator芯片结构 （3）在新型芯片结构上设计并制备单光子量子频率转化的微纳光子器件（4）量子点单光子发射和量子频率转化的表征.。通过本项目发展出一套混合光量子芯片的加工工艺，弄清楚单光子频率转化中各种噪声的物理机制，最终实验上演示在同一块芯片上实现高效单光子发射及其量子频率转换。为芯片上的量子信息处理过程，例如量子行走，光学泊松取样等提供高效量子光源。

量子光源是微纳光电子集成芯片和量子信息技术不可或缺的关键光子器件，其低效率和量子态难以按需调控极大地制约了量子光源的实际应用，高效按需可控量子光源的实现一直是该领域需要解决的重大挑战。目前，基于量子点的确定性量子光源为解决以上挑战提供了有效的解决途径，同时宽带可调的量子点量子光源也是使用过程中亟需解决的关键问题。本研究基于高质量外延生长的半导体量子点，制备出了芯片上集成的高性能固态纠缠量子光源，高偏振度单光子源，携带轨道角动量的单光子源，受激辐射操控的高性能单光子源，通讯波段的量子光源等。在量子频率转换方面，实现了集成芯片上的单光子频率转换器件，片上高Q非线性光学谐振器，无刻蚀铌酸锂－氮化硅薄膜非线性光子转换器件等片上集成光子器件。上述研究成果为芯片上的量子信息处理提供了高效的量子光源，也为加速我国的量子光源在量子信息处理中的研究及实用化进程提供参考。