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Quantum Computing, Communication, and Simulation

Quantum information processing and communication protocols based on time-bin entangled photonic qudits

Stefania Sciara, Hao Yu, Mario Chemnitz, Monika Monika, Farzam Nosrati, Agnes George, Nicola Montaut, Bennet Fischer, Benjamin Crockett, Robin Helsten, Benjamin Wetzel, Thorsten A. Goebel, Ria G. Krämer, Brent E. Little, Sai Tak Chu, Stefan Nolte, Zhiming Wang (396513), Jos x E Azana, William J. Munro, David Moss, Ulf Peschel, Rosario Lo Franco, Roberto Morandotti

Published Mar 5, 2026• 0 citations

Abstract

Encoding quantum information into time-bin entangled photons offers a physics-rich framework for both fundamental and applied quantum science. Here, we present two frameworks enabling the generation and manipulation of time-bin entangled photonic qudits for both fundamental and applied quantum information processing. The first framework consists of a scalable synthetic temporal photonic lattice implemented on a coupled fiber-loop system that is employed to explore and dynamically control the evolution of the discrete-time quantum walk of time-bin entangled photon states. The other framework consists of a modular, fiber-pigtailed, integrated photonic platform enabling the generation and processing of time-bin entangled qudits that were used to demonstrate the first Bennett-Brassard-Mermin 1992 QKD protocol extended to qudits. We operate the entangled qudits at processing speeds typical of standard telecommunication systems at 10s of GBaud.

DOI: 10.1117/12.3080571

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