Quantum key distribution based on frequency-time coding: security and feasibility

TL;DR

This paper proves the security of a frequency-time coding quantum key distribution protocol by linking it to a known secure protocol, extends it to an entanglement-based version, and demonstrates its practical feasibility with current technology.

Contribution

It establishes the security of FT-QKD via a connection to squeezed state protocols and introduces an entanglement-based version suitable for practical implementation.

Findings

Security of FT-QKD proven through connection to squeezed state protocols

Extended to an entanglement-based FT-QKD protocol

Simulation shows feasibility with current technology

Abstract

We establish a security proof of frequency-time coding quantum key distribution (FT-QKD) protocol by showing its connection to the squeezed state quantum key distribution protocol, which has been proven to be unconditionally secure. We also extend the prepare-and-measure FT-QKD protocol to an entanglement based FT-QKD protocol which is more appealing in practice. Furthermore, we propose a correlated frequency measurement scheme of entangled photon pair by using time resolving single photon detector. Simulation results show that the FT-QKD protocol can be implemented with today's technology.