Simplified quantum bit commitment using single photon nonlocality

TL;DR

This paper presents a simplified quantum bit commitment protocol leveraging single photon nonlocality, improving efficiency and immunity to certain cheating strategies by modifying the Mach-Zehnder interferometer setup.

Contribution

The authors simplify a previous QBC protocol by replacing symmetric beam splitters with asymmetric ones, enhancing feasibility and security against known no-go theorem strategies.

Findings

Protocol is immune to Mayers-Lo-Chau no-go theorem

Efficiency and feasibility are improved

Simplification does not compromise security

Abstract

We simplified our previously proposed quantum bit commitment (QBC) protocol based on the Mach-Zehnder interferometer, by replacing symmetric beam splitters with asymmetric ones. It eliminates the need for random sending time of the photons; thus, the feasibility and efficiency are both improved. The protocol is immune to the cheating strategy in the Mayers-Lo-Chau no-go theorem of unconditionally secure QBC, because the density matrices of the committed states do not satisfy a crucial condition on which the no-go theorem holds.