Robust Unconditionally Secure Quantum Key Distribution with Two Nonorthogonal and Uninformative States

TL;DR

This paper presents a new decoy-state method for quantum key distribution that enhances security against losses and noise without needing extra hardware, using uninformative states to prevent certain attacks.

Contribution

It introduces a novel decoy-state technique with uninformative states to improve robustness and security of QKD protocols without additional hardware.

Findings

Enhanced security against unambiguous state discrimination attacks.

No need for strong reference pulses or extra detectors.

Improved phase-error rate estimation.

Abstract

We introduce a novel form of decoy-state technique to make the single-photon Bennett 1992 protocol robust against losses and noise of a communication channel. Two uninformative states are prepared by the transmitter in order to prevent the unambiguous state discrimination attack and improve the phase-error rate estimation. The presented method does not require strong reference pulses, additional electronics or extra detectors for its implementation.