RAISE-TAQS: Towards a Quantum Cloud

量子科学技术有望实现强大的量子计算资源——量子云。虽然在这种网络中使用的量子处理节点和量子比特的确切实现仍然是研究和争论的主题，但节点之间的信息肯定会由光子携带。因此，将不同类型的量子比特与通信波长的光子相连接对于实现可扩展的分布式量子计算系统至关重要。这将导致高速电光调制器和微波光子系统的实现，这些系统将在经典和量子光网络中找到应用，以及光子规范场，拓扑光子学，强耦合量子系统等有趣和新兴物理现象的研究。这个项目的重点是超导量子技术，这是一个领先的量子计算平台，它面临着一个挑战：在远距离上有效地传输编码成微波光子的量子信息。该项目将为参与其中的学生提供一个独特的培训场所，并帮助培养新一代量子工程师和科学家。技术：该计划的目标是以单位效率实现低噪声微波到光光子的转换，然后利用这一点来演示超导量子比特和电信光子之间的量子态转移。利用量子干涉效应，超导量子比特将被用作微波光子的按需源。量子比特将与微波谐振器强耦合，实现在具有独特微波等离子体特性的少原子层超导薄膜中。这些因素包括低耗散、高非线性和异常高的动电感，导致信号传播异常缓慢。这将实现紧凑的微波谐振器，允许一端与量子比特强耦合，并与另一端的光学电路尺寸相匹配。微波光光子转换将基于电光学方法，使用超低损耗集成铌酸锂平台。该过程将通过使用结合两个光学谐振器和一个微波谐振器的三重谐振几何来增强。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。

Quantum science and technology promises realization of powerful quantum computational resource, aquantum cloud. While the exact implementation of quantum processing nodes and qubits to be used insuch networks are still the topic of research and debate, the information between the nodes will surely becarried by photons. Therefore, interfacing different types of qubits with photons at telecommunication wavelengths is critical for realization of scalable distributed quantum computational systems. This can lead to realization of high-speed electro-optic modulators and microwave photonicssystems that will find applications in classical and quantum optical networks, as well as the study ofinteresting and emerging physical phenomena including gauge field for photons, topological photonics,strongly-coupled quantum systems and so on. This program is focused on superconducting quantum technology, a leading quantum computing platform, that faces a challenge: efficient transfer of quantum information encoded into microwave photons over large distances.The program will provide a unique training ground for involved students and help train anew generation of quantum engineers and scientists.Technical: The goal of the proposed program is to achieve low-noise microwave-to-optical photon conversion with unity efficiency, and then leverage this to demonstrate quantum state transfer between superconducting qubit and a telecom photon. Superconducting qubit will be used as an on-demand source of microwave photons, by leveraging quantum interference effects. The qubit will be strongly coupled to a microwave resonator realized in few-atomic-layer superconducting films that exhibit unique microwave-plasmonic properties. These include low dissipation, high nonlinearity, and exceptionally high kinetic inductance, resulting in extraordinarily slow signal propagation. This will enable realization of compact microwave resonators that allow for strong coupling to a qubit on one end, and that match the dimensions of the optical circuits on the other end. Microwave-to-optical photon conversion will be based on the electrooptics approach using ultra low loss integrated lithium-niobate platform. The process will be enhanced by using triply resonant geometry that combines two optical and one microwave resonator.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.