Collaborative Research: NeTS: Small: Models and Algorithms for Hybrid Continuous-Discrete Variable Quantum Networking

Quantum information processing brings fundamental new paradigms for sensing, computing and communication. It will enable foundational innovations in many fields from physics to chemistry, to energy and finance, to secure digital infrastructure, and more. However, the ability to communicate quantum information effectively and efficiently across distance is a crucial pre-requisite for reaping the benefits of many quantum applications, including large-scale quantum computing, distributed quantum sensing and quantum-enhanced (secure) communications. Building on top of recent advances in developing a quantum network along two separate lines, this project will develop a new hybrid architecture that will reap the benefits of both continuous-variable and discrete-variable quantum networking, and design algorithms and protocols to enable high-rate and high-fidelity distribution of quantum entanglement resources across long distances and for various future quantum applications. The research will result in concepts and tools to empower the future quantum infrastructure and ecosystem. The project will help develop the future quantum workforce by actively involving and broadening participation from high school and undergraduate students in quantum-related research.The key innovation of this project is a new hybrid continuous-discrete variable quantum network architecture, and a suite of models, algorithms and protocols, for understanding and enabling high-rate high-fidelity entanglement distribution for quantum computing, sensing and communication applications. To achieve this goal, the proposed research encompasses both theoretical and practical considerations around: how to model and optimize physical processes and protocols for generating and manipulating continuous- and discrete-variable entangled states, how to measure and optimize performance metrics of a hybrid continuous-discrete variable quantum network system with scalability, and what application-level utilities might such a hybrid network enable compared to an infrastructure using either continuous- or discrete-variable components alone. To answer these questions, the expected contributions of this project are: (1) developing new models and protocols for hybrid continuous- and discrete-variable entanglement generation, manipulation and conversion; (2) designing a generic hypergraph-based framework for optimizing the design of a hybrid network for end-to-end entanglement distribution; (3) developing models and algorithms to support future quantum applications in computing, communication and sensing with the hybrid architecture. The outcomes of this research will inform and empower the development of future quantum network technologies, by significantly expanding the flexibility in combining and utilizing heterogeneous devices and technologies in an end-to-end manner.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.