Unconditional Authentication in Quantum Key Distribution via Hybrid Entangled Physical Unclonable Functions

Authors

Abstract

Quantum Key Distribution (QKD) enables Information-Theoretically Secure (ITS) key exchange, robust even against future quantum computing threats. However, a fundamental limitation of QKD is the requirement for an authenticated classical channel, which necessitates a pre-shared secret key. In this letter, we address this dependency by integrating a Hybrid Physical Unclonable Function (PUF) protocol. We demonstrate that this PUF-based method generates an ITS initial key under minimal explicit hardware assumptions. This approach establishes a fully ITS-authenticated QKD protocol that relies solely on hardware assumptions, effectively eliminating the need for manually pre-shared secrets. This represents a significant step toward practical realization of quantum network protocols using lightweight, readily available hardware assumptions, without weakening security guarantees.