QuIC - TaQS: Interconnects for a Superconducting-Atomic Hybrid Quantum Network

目前设想的“量子互联网”基础设施由连接在一起的量子设备组成，如量子计算机、模拟器和传感器，这些设备可能位于相距遥远的地理位置。在这些设备之间分配量子信息将是利用它们并获得相对于经典信息技术的技术优势，并使广泛的研究人员和商业用户能够访问的关键。这项研究计划的目标是开发和演示基本的互连技术，这些技术共同实现了相距遥远的量子计算节点之间的远程链接。具体地说，开发了三种互连：第一，频率转换器，将量子信号从低温操作的固态量子比特转换为可以通过光纤网络发送的光信号。第二，可以扩大光量子信号传输范围的中继器设备。最后，一种用于低温量子位的固态存储器，它将允许容忍大规模网络中的延迟。总而言之，这些互联技术的实现是建立量子设备之间远距离连接的关键踏脚石。作为该项目的一部分，私人投资机构正在开发关于量子工程和量子网络主题的教育和推广计划，并与行业和国家实验室合作伙伴合作。该研究项目旨在通过联合理论和实验努力解决三个截然不同和互补的量子互连计划。微波-光学转换对于在非低温下远距离传输超导量子比特产生的量子态至关重要。为此，超导量子电路与光学机械晶体相连接，这种晶体可以将微波辐射耦合到电信频段的光。该转换系统发射的辐射可以通过量子干涉与Yb原子发射的光学光子相接。Yb原子阵列是原子量子信息处理的一个很有前途的平台，将被用来实现量子中继器。第三个互连是在超导量子比特和掺杂晶体中的稀土离子自旋之间。这种自旋是实现微波领域超长相干时间的一种很有前途的资源。由于光转换和量子干涉方案是高度概率的，需要非常好的量子存储器来容忍网络中产生的延迟。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

A currently envisioned ‘quantum internet’ infrastructure consists of linked quantum devices, such as quantum computers, simulators, and sensors, that may be located in widely separated geographical locations. Distributing quantum information between these devices will be key for utilizing them with a technological advantage over classical information technologies, and making the accessible to a wide range of researchers and commercial users. The goal of this research program is the development and demonstration of essential interconnect technologies that together enable long-range links between widely separated quantum computing nodes. Specifically, three interconnects are developed: First, a frequency converter that converts quantum signals from cryogenically operated solid-state qubits to optical signals that can be sent through fiber networks. Second, a repeater device that can extend the range of optical quantum signals transmitted. And finally, a solid-state memory for cryogenic qubits that will allow tolerating latencies in large-scale networks. Together, the realization of these interconnect technologies are a critical stepping stone for establishing long-distance connections between quantum devices. As part of the project, the PIs are developing educational and outreach programs on the topic of quantum engineering and quantum networking, and are collaborating with industry and national lab partners.The research project targets three distinct and complementary quantum interconnection schemes that are tackled with a joint theoretical and experimental effort. Microwave-to-optical conversion is crucial for transmitting quantum states originating from superconducting qubits over large distances at non-cryogenic temperatures. To that end, superconducting quantum circuits are interfaced with optomechanical crystals that can couple microwave radiation to optical light in the telecom band. The radiation emitted by this converter system can be interfaced with optical photons emitted by Yb atoms through quantum interference. Arrays of Yb atoms are a promising platform for atomic quantum information processing and will be used to realize a quantum repeater. The third interconnect is between superconducting qubits and rare-earth ion spins in doped crystals. Such spins are a promising resource for realizing ultra-long coherence times in the microwave domain. Because optical conversion as well as quantum interference schemes are highly probabilistic, very good quantum memory is required to tolerate the resulting latency in a network.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.