Multi-channel entanglement distribution using spatial multiplexing from four-wave mixing in atomic vapor

TL;DR

This paper demonstrates the generation of multiple pairs of entangled light modes via four-wave mixing in atomic vapor, enabling simultaneous secure key distribution and secret sharing among multiple parties.

Contribution

It introduces a method to spatially multiplex entangled modes from atomic vapor for multi-party quantum communication.

Findings

Successfully generated three pairs of entangled modes

Verified correlations through continuous-variable measurements

Demonstrated a classical four-party secret sharing scheme

Abstract

Four-wave mixing in atomic vapor allows for the generation of multi-spatial-mode states of light containing many pairs of two-mode entangled vacuum beams. This in principle can be used to send independent secure keys to multiple parties simultaneously using a single light source. In our experiment, we demonstrate this spatial multiplexing of information by selecting three independent pairs of entangled modes and performing continuous-variable measurements to verify the correlations between entangled partners. In this way, we generate three independent pairs of correlated random bit streams that could be used as secure keys. We then demonstrate a classical four-party secret sharing scheme as an example for how this spatially multiplexed source could be used.