ExpandQISE Track 1: Quantum information exchange over spatially-multimode and multi-core optical fibers

非技术描述：量子通信利用基本物理定律在不可信网络上安全地交换私有信息，并在远程网络节点之间建立量子相关性，可用于高性能分布式量子计算和超精密量子传感。量子通信链路的容量受到连接节点的光纤不可避免的损耗的限制，在给定距离上增加量子信息交换速率的唯一方法是增加信息传输的自由度（模式）的数量。虽然偏振和频率/时间模式已经受到了很多关注，但在长光纤链路上进行量子信息交换的一个尚未开发的资源是光在少模、多模和多芯光纤中的空间自由度。在这个项目中，研究小组利用光的空间自由度在光纤中长距离传输量子信息。研究了几种类型的高容量量子通信链路，从一组完全独立的空间量子信道到使用空间模式进行高维数据编码的链路。该项目将拥有新生量子信息科学与技术（QISE）项目的德克萨斯大学阿灵顿分校与西北大学成熟且充满活力的QISE研究工作结合起来。通过联合研究和学生交流，以及与工业和全球合作伙伴的合作，各级学生，包括那些代表性不足的群体，正在接受量子科学和光通信前沿的培训。这项合作工作以及相关的广泛的公众和K-12外展活动，如高中夏令营和工程周的开放实验室参观和演示，旨在将德克萨斯大学阿灵顿分校建立为北德克萨斯州新兴和富有成效的QISE研究社区的中心。技术描述：该项目的目标是通过利用光纤的空间自由度来增加量子通信容量。它将经典空分复用方法扩展到量子领域，开发了几种类型的高容量量子通信链路。这些范围从一组完全独立的空间量子信道到跨许多光纤模式或核心保持完全空间相干的链路，用于传输高维空间希尔伯特空间编码的量子信息。该项目采用了一种系统的方法来实时表征和反演光纤的输入输出传输矩阵，以实现在地铁尺度距离上的并行通道或高维量子比特的传输，从而大大提高了这种距离下的量子通信容量或速率。这些技术还可以使空间宽带量子态（量子图像）在多模光纤的公里尺度上传输，这在量子传感和计量应用中是有用的。这项工作让学生与几个工业合作伙伴一起开发定制的少模和多芯光纤，以及光纤进/出耦合器。所开发方法的现场测试将在已安装的光纤上进行。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Non-technical description:Quantum communication uses fundamental laws of physics to securely exchange private information over untrusted networks and to establish quantum correlations among distant network nodes, which could be used for high-performance distributed quantum computing and ultra-precise quantum sensing. The capacity of quantum communication links is limited by the unavoidable losses of optical fibers connecting the nodes, and the only way to grow the quantum information exchange rate at a given distance is to increase the number of degrees of freedom (modes) over which the information is transmitted. While polarization and frequency / time modes have already received a lot of attention, one untapped resource for quantum information exchange over long fiber links is the spatial degrees of freedom of light in few-mode, multimode, and multi-core optical fibers. In this project, the research team harnesses the spatial degrees of freedom of light for carrying the quantum information over significant distances in optical fibers. Several types of high-capacity quantum communication links are investigated, ranging from a set of totally independent spatial quantum channels to links using spatial modes for high-dimensional data encoding. The project pairs University of Texas at Arlington, which has a nascent Quantum Information Science and Technology (QISE) program, with well-established and vibrant QISE research effort at Northwestern University. Through the joint research and student exchange, as well as collaboration with industrial and worldwide partners, the students of all levels, including those of underrepresented groups, are being trained at the forefronts of quantum science and optical communications. This collaborative work and the associated broad public and K-12 outreach activities, such as high-school summer camps and Engineering Week’s open lab visits and demos, aim to establish University of Texas at Arlington as a center for the emerging and productive QISE research community in North Texas. Technical description:This project’s goal is to increase the quantum communication capacity by exploiting spatial degrees of freedom of optical fibers. It extends the methods used in classical space-division multiplexing to the quantum domain to develop several types of high-capacity quantum communication links. These range from a set of totally independent spatial quantum channels to links maintaining full spatial coherence across many fiber modes or cores for transmission of quantum information encoded in high-dimensional spatial Hilbert space. The project employs a systematic approach to real-time characterization and inversion of the input-output transfer matrix of an optical fiber to enable the delivery of parallel-channel or high-dimensional qubits over metroscale distances, thus dramatically increasing the quantum communication capacity or rate at such reach. These techniques may also enable the transmission of spatially-broadband quantum states (quantum images) over km-scale lengths of multimode fiber, which can be useful in quantum sensing and metrology applications. The work engages the students with several industrial partners on development of customized few-mode and multi-core fibers, as well as fiber in/out couplers. A field-test of the developed methods is to be conducted over installed fibers.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.