Hidden multi-dimensional modulation side channels in quantum protocols

TL;DR

This paper reveals that practical quantum devices often perform hidden multi-dimensional modulations, creating security loopholes in quantum protocols like quantum key distribution and blind quantum computing.

Contribution

It uncovers the existence of hidden multi-dimensional modulation side channels in practical quantum devices, challenging the assumed security assumptions.

Findings

Hidden multi-dimensional modulation occurs in practical quantum devices.

Such modulations create security loopholes in quantum cryptographic protocols.

The results impact the security analysis of quantum communication systems.

Abstract

Quantum protocols including quantum key distribution and blind quantum computing often require the preparation of quantum states of known dimensions. Here, we show that, rather surprisingly, hidden multi-dimensional modulation is often performed by practical devices. This violates the dimensional assumption in quantum protocols, thus creating side channels and security loopholes. Our work has important impacts on the security of quantum cryptographic protocols.