ExpandQISE: Track 1: Virtual Quantum Networks: From Foundations to Field Tests

Project Synopsis


      The emergence of quantum networks has sparked a technological revolution envisaged to shift the landscape of communication, sensing, and computing in the forthcoming decades. While ongoing efforts in building quantum networks are broad, immense, and even like ``arms race'', existing quantum network systems are still local, small-scale, and application-specific (e.g., designed for quantum key distribution), which is reminiscent of the era of internet onset. Looking ahead, the expansion of quantum networks, if without thoughtful planning, will inevitably lead us into the same pitfalls as classical internet such as network ossification and resource wastes.

      The goal of this project is to develop a general-purpose, open-access, and programmable quantum network prototype for the quantum information science and engineering (QISE) community to experiment new quantum technologies and train teachers/students of all majors, thereby accomplishing the vision of coordinating diverse research efforts and expanding the QISE workforce. The key methodology to be applied is virtualization that will turn a physical quantum network fabric into multiple independent software-controlled network overlays for concurrent and hardware-agnostic network access. An overview of the proposed research & education activities are displayed in Figure 1.

      (1): Establish the Foundation for VQNs: Architecture Design;

      (2): Access VQNs Efficiently: Protocol Design;

      (3): Implement and Evaluate the VQN (with Education Integration).

      This project will be based on a quantum network testbed in the University of Arizona (UA), which was developed by co-PI Zhang's lab and colleagues. The testbed is shown in Figure 2. Specifically, the INQUIRE testbed consists of 14 network nodes residing in 6 buildings across the UA campus, connected by more than 100 optical fibers and a free-space line-of-sight link, as shown in Figure 2a. At present, the key functionalities of INQUIRE include the generation and distribution of entangled-photons, remote access to single-photon detectors, and scheduling and routing of quantum resources. As a precursor of VQNs, the INQUIRE testbed currently serves as a quantum internet service provider (qISP) that is fully automated and centrally managed by the Agilent iLab platform. Quantum-network users remotely log into the iLab platform to request access to the quantum resources including entangled photons and single-photon detectors, as illustrated by Figure 2b. The qISP of INQUIRE shares, manages, and maintains quantum resources for a large number of network users in a time-multiplexed manner. The capability qISP of INQUIRE can be substantially enriched by the new VQN architecture, protocols, and applications to be pursued in this project.

Personnel and Collaborators


  • Students
    • Stuart Pelletier (Fall 2022 - Fall 2024 )
    MS., Computer Science, NC State University
    Email: sopellet at ncsu dot edu
    Role: Theory and optimization
    Tingxiang Ji (Fall 2023 - )
    MS., Computer Science, Nanjing Tech University
    Email: tji2 at ncsu dot edu
    Role: Quantum device modeling and control
    Raj K. Madhu (Spring 2024 - Spring 2025)
    BS., Indus University, India
    Email: rmadhu3 at ncsu dot edu
    Research Interests: Cloud Services for Quantum Network Testbed
    Role: Cloud API design


  • Collaborators
    • Dr. Zheshen Zhang (co-PI)
    Associate Professor
    Department of Electrical Engineering and Computer Science
    University of Michigan
    Email: zszh at umich dot edu

    Research Progress


  • Publications
      [4] The Road to Quantum Internet: Progress in Quantum Network Testbeds and Major Demonstrations
            J. Liu, T. Le, T. Ji, R. Yu, D. Darfurnik, G. Byrd, and D. Stancil, Elsevier Progress in Quantum Electronics (PQE), Vol. 99, 100551, 2025.
      [3] Distributing Arbitrary Quantum Cluster States by Graph Transformation
            T. Ji, J. Liu, and Z. Zhang, IEEE Transactions on Communications (IEEE TCOMM), Under Review. [arXiv]
      [2] Qubit Recycling in Entanglement Distillation
              S. Pelletier, R. Yu, G. Rouskas, J. Liu, 2023 IEEE International Conference on Quantum Computing and Engineering. (IEEE QCE'23).
      [1] A Heuristic Remote Entanglement Distribution Algorithm on Memory-Limited Quantum Paths
              L. Chen, K. Xue, J. Li, N. Yu, R. Li, J. Liu, Q. Sun J. Lu, IEEE Transactions on Communications, Vol. 70, No. 11, pp. 7491-7504, 2022. (IEEE TCOM).
  • Thesis and Dissertation
      [1] Title: Software Virtualization and Resource Allocation in Quantum Networks (MS Thesis)
            Mr. Raj Madhu, March 06, 2025.

    • Education and Outreach Activities


  • New Curriculum
      CSC/ECE 591/791: Quantum Communications and Network
      Course Syllabus: [this link]
      Description: Quantum communications is no longer a myth but a revolutionary technology that is just around the corner. This course covers the cutting-edge topics of quantum communications and network (QCN). The objective of this course is to provide students with the theoretical foundation, simulation methods, and research frontiers of QCN through pedagogical activities such as lecturing, paper reading and presentation, and projects.
            The covered topics by this course include (but not limited to) quantum gates/operations, entanglement, teleportation, error control, purification, metrics for performance assessment, optical channel modeling, network graphs and quantum graph states, and quantum applications.
      Semesters of Offering: Fall 2022, Spring 2023
      Enrollment: 10 (Fall'22), 9 (Spring'23)
  • Outreach Activities
      [3] Protocol Design For Quantum Entanglement Distribution Networks (invited talk)
            Triangle Quantum Seminar, UNC-NCSU-Duke, Raleigh, 2025.
      [2] Entanglement Distribution Networks: From the Lens of Protocol Design (invited talk)
            Quantum Information Technology Workshop, University of Michigan, Ann Arbor, 2025.
      [1] Quantum Networking for Distributed Quantum Computing Systems (panel discussion)
            NSF CSR PI Meeting, Duke University, Durham, 2023.

    • Disclaimer


    Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.
    Copyright © Jianqing Liu | "You must be the change you wish to see in the world."