ICCCAS 2025 Invited Speaker

Salem Hegazy

Zewail City of Science and Technology, Egypt

Biography: Salem F. Hegazy (Member, IEEE) received the B.Sc. (Hons.), Diploma, and M.Sc. degrees in electronics and communications engineering from Cairo University, in 2002, 2006, and 2011, respectively, and the Ph.D. degree in quantum optics and nonlinear optics through a joint-supervision scheme between CREOL, The College of Optics and Photonics, University of Central Florida, and the National Institute of Laser Enhanced Sciences, Cairo University, in 2017. He serves as an Associate Professor with the National Institute of Laser Enhanced Sciences, Cairo University, and is the Founding Director of the Quantum Communications and Cryptography Lab (QCCL) at the Center for Photonics and Smart Materials, Zewail City of Science and Technology. His research interests include optical processing of quantum computation and quantum information, practical security of quantum cryptography, photonic entanglement, optical communications, optical chaos-based systems, and optical image encryption. He was the recipient of the Egyptian State Encouragement Award in Engineering Sciences in 2019 and State Award for Organizations and Individuals in Scientific and Technological Innovation in 2021.
Speech Title: Secure Quantum Key Distribution Against Detector-Control Attacks via Randomized Gateway
Abstract: Practical implementations of quantum key distribution (QKD) have been shown to be subject to various detector side-channel attacks that compromise the promised unconditional security. Most notable is a general class of attacks adopting the use of faked-state photons as in the detector-control and, more broadly, the intercept-resend attacks.
In this talk, we present a simple scheme to overcome such class of attacks: A legitimate user, Bob, uses a polarization randomizer at his gateway to distort an ancillary polarization of a phase-encoded photon in a bidirectional QKD configuration. Passing through the randomizer once on the way to his partner, Alice, and again in the opposite direction, the polarization qubit of the genuine photon is immune to randomization. However, the polarization state of a photon from an intruder, Eve, to Bob is randomized and hence directed to a detector in a different path, whereupon it triggers an alert. We demonstrate theoretically and experimentally that, using commercial off-the-shelf detectors, it can be made impossible for Eve to avoid triggering the alert, no matter what faked-state of light she uses.