Quantum photonics devices for quantum communications

“量子互联网”通常被认为是下一代网络，其中共享量子信号可以实现高度安全通信，与远程量子计算机接口和量子增强计量等应用。时至今日，许多不同的物理系统都被考虑用于量子信息。虽然目前还不清楚哪个系统最适合领导量子信息革命，但很明显，光子将在量子设备之间的通信中发挥重要作用。我计划研究的基于光子的量子信息系统涉及到量子通信、量子隐形传态和量子计算，也涉及到基础的量子纠缠实验。***我提出的研究主要有两条：***第一，研究大距离链路上量子通信和纠缠的实现。具体来说，我正在领导一项名为“量子加密和科学卫星”的任务提案，在过去与加拿大航天局和工业界的合作伙伴进行的几项研究中，我们开发了一种使用当今卫星和光通信技术的设计，它将实现地面到空间的量子通信系统，并使用低地球轨道卫星连接地球上的任何位置。具体来说，在这个拟议的项目中，我将研究用于地面测试的光子产生和光子探测的高度稳定和紧凑的源。***第二，实现和研究适合于少量光子相互作用的光学非线性。我计划研究的主要候选系统是波导或微光学系统，要么是强泵浦的三阶非线性（如硫系玻璃），要么是高二阶非线性（如铌酸锂晶体）。这些光子转换器在量子通信中具有各种重要应用，使高度安全的量子密钥分发具有设备独立性，并使无漏洞的贝尔测试和认证量子随机数成为可能。此外，高光学非线性也将有助于我对纠缠辅助双光子吸收的研究，这可能在双光子显微镜和量子计算中有应用。***通过对量子光子学应用的研究，我的目标是使“量子互联网”更接近现实

The "Quantum Internet" is often considered the future generation of networking, where the shared quantum signals enable applications such as highly secure communications, interfacing to remote quantum computers and quantum enhanced metrology. As of today, many different physical systems are considered for quantum information. While it has yet to emerge which system is best suited to lead the quantum information revolution, it is clear that photons will play an important role in the communication between quantum devices. The photonic- based quantum information systems that I plan to study are relevant for quantum communication, quantum teleportation and quantum computing, and also fundamental quantum entanglement experiments.  ***The two main lines of my proposed research are:***First, research on the implementations of quantum communications and entanglement over large distance links. Specifically, I am leading the mission proposal called "Quantum Encryption and Science Satellite, where in several past studies with the Canadian Space Agency and partners from industry, we developed a design using today's technology for satellites and optical communications, which would implement a ground to space quantum communication system, and use a low- Earth -orbiting satellite to connect essentially any location on our Globe. Specifically, in this proposed project I will work on the highly stable and compact sources for the photon generation and photon detection on ground tests. ***Second, to implement and study optical nonlinearities suitable for few photon interactions. The main candidate systems I plan to study are waveguides or micro--optical systems, either strongly pumped third-order nonlinearities (such as Chalcogenide Glasses) or a high second--order nonlinearity (such as Lithium-Niobate crystals). These photon converters have various important applications in quantum communications, enable highly secure quantum key distribution with device independence, and enable loophole free Bell--tests and certified quantum random numbers. Furthermore, the high optical nonlinearities will also assist my research on entanglement assisted two-photon absorption, which could have applications in two-photon microscopy as well as in quantum computing. ***With my research on quantum photonics applications I aim to bring the "Quantum Internet" closer to reality.**