Quantum benchmarks for the storage or transmission of quantum light from minimal resources

TL;DR

This paper compares quantum benchmarks for transmitting or storing quantum light, finding Gaussian-based criteria most noise-resilient and proposing a resource-efficient benchmark using only three coherent states and homodyne detection.

Contribution

It introduces a new, resource-efficient benchmark based on three coherent states and homodyne detection, simplifying experimental requirements for quantum light transmission and storage.

Findings

Gaussian-based benchmarks are most noise-resilient

Proposed benchmark requires only three coherent states

Random phases eliminate the need for active modulation

Abstract

We investigate several recently published benchmark criteria for storage or transmission of continuous-variable quantum information. A comparison reveals that criteria based on a Gaussian distribution of coherent states are most resilient to noise. We then address the issue of experimental resources and derive an equally strong benchmark, solely based on three coherent states and homodyne detection. This benchmark is further simplified in the presence of naturally occurring random phases, which remove the need for active input-state modulation.