Quantum photonics devices for quantum communications

量子互联网通常被认为是未来一代的网络，其中共享的量子信号使诸如高度安全的通信、与远程量子计算机的接口和量子增强计量学等应用成为可能。到今天为止，许多不同的物理系统被考虑用于量子信息。虽然目前还没有出现哪种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与量子通信、量子隐形传态和量子计算有关，也与基本的量子纠缠实验有关。*我提出的研究的两条主线是：*第一，研究大距离链路上的量子通信和纠缠的实现。具体地说，我正在领导名为“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合作伙伴的几项研究中，我们开发了一种利用当今卫星和光通信技术的设计，它将实现一个地面到空间的量子通信系统，并使用一颗近地轨道的卫星基本上连接我们地球上的任何位置。具体地说，在这个拟议的项目中，我将致力于高稳定和紧凑的光源，用于地面测试中的光子产生和光子探测。第二，实现和研究适合于少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，要么是强抽运的三阶非线性(如硫化物玻璃)，要么是高二阶非线性(如Lithium-Nobate晶体)。这些光子转换器在量子通信中有各种重要的应用，实现了与设备无关的高度安全的量子密钥分发，并实现了无漏洞的贝尔测试和认证的量子随机数。此外，高度的光学非线性也将有助于我对纠缠辅助的双光子吸收的研究，这可能在双光子显微镜和量子计算中有应用。*通过我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.**