Photonics & Electromagnetics Research Symposium - Spring (PIERS-Spring)

Optimizing Intruder Evasion and Key Recovery on BB84 Quantum Protocol via Varying Rotational Angles with a Universal Quantum Copying Machine

Yousef Ahmed Y. Altaher

Published May 4, 2025• 0 citations

Abstract

The no-cloning theorem provided a security feature that enabled the BB84 protocol to be a possible quantum protocol for secure key exchange. A possible method to undermine the security of the BB84 exists by utilizing a UQCM to imperfectly copy the qubits. However, due to the introduced errors, detections of an intruder using a UQCM is possible, in addition to the imperfect recovered key by the intruder. In this paper, a simulation of an intruder intercepting a 5 -qubit BB84 protocol execution with 1000 randomly generated sets of angles, 100 -time of BB84 simulation, for each set, is used to estimate the probability of detection and key recovery with a UQCM. Despite that a UQCM is universally optimized with the values on the 1998 paper of Vladimr R. Buzek and Mark Hillery, the simulations provided different values that can reduce the detection rate while increasing the probability of a successful key recovery. Moreover, there are multiple rotational angles that provides similar key recovery probability with varying degrees of discoverability.

DOI: 10.1109/piers-spring66516.2025.11276559

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