CAREER: Integrated sources of multiphoton entanglement for enabling quantum interconnects

非技术性：在寻求将量子技术推向前沿的过程中，将量子系统扩大到实际应用的挑战迫在眉睫。光子作为量子互连，通过将更小的量子系统编织在一起来增强整体量子计算能力，提供了一种解决方案，类似于经典的集群计算机。然而，实现实用的光子量子互连取决于纠缠多光子源的可用性，该多光子源具有所需的亮度、质量和纠缠粒子数量。该项目的核心目标是改造量子光源，特别是旨在创建高效和高质量的多光子纠缠态。这项研究利用了主要研究人员在芯片级单光子源方面取得的进展，这种源使用嵌入到纳米级光子结构中的半导体量子点来实现稳健性和可扩展性。为了将单光子源的这种性能转化为多光子纠缠，材料和器件级建模方面的创新将与精确的光谱和量子比特控制相结合，以表征和抑制量子比特中的噪声。这一全面的方法寻求在短期内建立光子量子互连的实用性和弹性。与这些科学追求相辅相成的是，该项目非常重视教育，力求在学生中培养强大的科学认同感和科学界的归属感。通过跨学科论坛和量子推广计划，该项目旨在通过为吸引人的量子技术领域的学生互动和合作提供独特的机会，促进STEM中代表性不足的社区的招募和保留。技术：该提议的中心目标是设计和实现一个芯片上的多光子纠缠态来源，以满足实现实际量子互连对效率、保真度和可扩展性的苛刻要求。为了实现这一目标，我们将控制和利用光学活性单量子点和耦合到光子晶体波导的隧道耦合量子点中的自旋-光子相互作用，以实现高收集效率，同时利用局部液滴刻蚀量子点的低噪声特性。通过(1)通过新颖的理论模型和实验建立光子纯度和纠缠保真度的基本极限；(2)解决纳米结构中自旋-光子相互作用的基本物理知识空白；(3)展示芯片集成量子光源中一维和二维多光子纠缠的产生。本项目由电子、光子和磁器件(EPMD)计划联合资助。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。

Nontechnical: In the quest to bring quantum technologies to the forefront, the challenge of scaling up quantum systems for practical applications looms large. Photons, serving as quantum interconnects, offer a solution by weaving together smaller quantum systems to enhance the overall quantum computational power, akin to classical cluster computers. However, the realization of practical photonic quantum interconnects hinges on the availability of entangled multiphoton sources with the required brightness, quality, and number of entangled particles. This project's core objective is to transform quantum light sources, specifically aiming to create efficient and high-quality multiphoton entangled states. The research leverages the advances made by the lead researchers in chip-scale single-photon sources that employ semiconductor quantum dots embedded in nanofabricated photonic structures to achieve robustness and scalability. To translate this performance of single-photon sources to multiphoton entanglement, innovations in material and device level modeling will be coupled with precise spectroscopy and qubit control to characterize and suppress noise in qubits. This comprehensive approach seeks to establish the practicality and resilience of photonic quantum interconnects in the near term. Complementing these scientific pursuits, the project places a strong emphasis on education, seeking to foster a robust science identity and a sense of belonging within the scientific community among students. Through an interdisciplinary forum and a quantum outreach program, the project aims to enhance the recruitment and retention of underrepresented communities in STEM by providing unique opportunities for student interaction and collaboration in the captivating field of quantum technologies.Technical: The central objective of this proposal is to design and implement an on-chip source of multiphoton entangled states that satisfy the steep demands on efficiency, fidelity, and scalability for realizing practical quantum interconnects. To achieve this, we will control and harness spin-photon interactions in optically active single quantum dots and tunnel-coupled quantum dots coupled to photonic crystal waveguides to achieve high collection efficiency, while leveraging low-noise properties of local-droplet etched quantum dots. Accomplishing the research tasks of this proposal will advance the understanding and lay the foundation for robust and efficient quantum interconnects by (1) establishing the fundamental limits on photon purity and entanglement fidelity through novel theoretical models and experiments, (2) addressing the knowledge gaps in the fundamental physics of spin-photon interactions in nanostructures, and (3) demonstrating 1D and 2D multiphoton entanglement generation in a chip-integrated quantum light source.This project is jointly funded by Electronic, Photonic, and Magnetic Devices (EPMD) Program of the Division of Electrical, Communications and Cyber Systems (ECCS) and the Established Program to Stimulate Competitive Research (EPSCoR).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.