Improved Direct Counterfactual Quantum Communication

TL;DR

This paper introduces an improved counterfactual quantum communication protocol that reduces the negative effects of chaining, leading to faster transmission and better noise resilience by employing quantum interference.

Contribution

The authors propose a novel protocol that eliminates the chained structure, enhancing counterfactuality and robustness against noise compared to previous methods.

Findings

Reduced transmission time for single bits

Enhanced noise tolerance of the protocol

Achieved better counterfactuality in practical scenarios

Abstract

Recently, a novel direct counterfactual quantum communication protocol was proposed using chained quantum Zeno effect. We found that this protocol is far from being widely used in practical channels, due to the side effect of 'chained', which leads to a dramatic increase of the equivalent optical distance between Alice and Bob. Therefore, not only the transmission time of a single bit increases in multiple times, but also the protocol is more sensitive to the noise. Here, we proposed an improved protocol, in which quantum interference is employed to destroy the nested structure induced by 'chained' effect. Moreover, we proved that a better counterfactuality is easier to be achieved, and showed that our protocol outperforms the former in the presence of noises.