Coherent Communication with Linear Optics

TL;DR

This paper demonstrates how to implement continuous-variable coherent protocols using linear optics, analyzing noise effects, proposing new protocols, and detailing experimental verification methods.

Contribution

It introduces two new protocols for implementing a coherent channel, improves resource efficiency, and connects coherent channels with nonlocal quantum nondemolition interactions.

Findings

Bounded noise accumulation in realistic optical devices

Proposed a more resource-efficient protocol for nonlocal quantum nondemolition interaction

Outlined experimental implementation and verification of continuous-variable coherent teleportation

Abstract

We show how to implement several continuous-variable coherent protocols with linear optics. Noise can accumulate when implementing each coherent protocol with realistic optical devices. Our analysis bounds the level of noise accumulation. We highlight the connection between a coherent channel and a nonlocal quantum nondemolition interaction and give two new protocols that implement a coherent channel. One protocol is superior to a previous method for a nonlocal quantum nondemolition interaction because it requires fewer communication resources. We then show how continuous-variable coherent superdense coding implements two nonlocal quantum nondemolition interactions with a quantum channel and bipartite entanglement. We finally show how to implement continuous-variable coherent teleportation experimentally and provide a way to verify the correctness of its operation.