Quantum networks extend quantum communication from point-to-point links to interconnected systems capable of distributing quantum information across many users and locations. Realizing such networks requires not only reliable communication channels but also efficient methods for generating, distributing, and protecting multipartite quantum resources.

Our research investigates the theoretical foundations of quantum networks, with particular emphasis on how multipartite entanglement, quantum error correction, and higher-dimensional quantum systems can be integrated into scalable communication architectures. We are also interested in the interplay between network structure and communication complexity.

Research topics:

• Photonic state generation — Developing theoretical methods for generating multipartite photonic states, which are particularly well suited for long-distance quantum communication.
• Quantum repeaters and long-distance communication — Studying architectures and resource requirements for distributing entanglement over large distances in realistic communication networks.
• Network architectures — Investigating architectures for secure communication and scalable quantum networking, and also understanding the resources required for quantum communication tasks and how network structure influences their performance.
• Classical and quantum network models — Exploring how concepts from classical network theory can be adapted to the design and analysis of future quantum networks.

Selected publications:

• "Graph-State Circuit Blocks control Entanglement and Scrambling Velocities", Ch. Rao, H. Sahu, A. Bhattacharya, S. Ahmad Rather, M. Flory, and Z. Raissi, arXiv:2605.11076.
• "Deterministic generation of qudit photonic graph states from quantum emitters", Z. Raissi, E. Barnes, and S. E. Economou, PRX Quantum 5, 020346 (2024).
• "Extracting perfect GHZ states from imperfect weighted graph states via entanglement concentration", R. Frantzeskakis, C. Liu, Z. Raissi, E. Barnes, and S. E. Economou, Phys. Rev. Research 5, 023124 (2023).
• "Stochastic local operations with classical communication of absolutely maximally entangled states", A. Burchardt, Z. Raissi, Phys. Rev. A 102, 022413 (2020).
• "Creating Maximally Entangled States by Gluing", Z. Raissi, and V. Karimipour, Quant. Inf. Process. 16, 81 (2017).
• "Constructing entanglement measures for fermions", M. Johansson, and Z. Raissi, Phys. Rev. A 94, 042319 (2016).