# Inter-Core Crosstalk Impact of Classical Channels on CV-QKD in Multicore Fiber Transmission

## TL;DR

This paper experimentally investigates how classical channel crosstalk in multicore fibers affects the excess noise in continuous-variable quantum key distribution, impacting secret key rates.

## Contribution

It provides the first experimental characterization of crosstalk-induced excess noise in CV-QKD within multicore fiber systems.

## Key findings

- Crosstalk contributes significantly to excess noise in CV-QKD.
- Secret key rates are reduced due to crosstalk-induced noise.
- The study offers insights for integrating quantum and classical channels in multicore fibers.

## Abstract

Crosstalk-induced excess noise is experimentally characterized for continuous-variable quantum key distribution, spatially multiplexed with WDM PM-16QAM channels in a 19-core fiber. The measured noise-sources are used to estimate the secret key rates for different wavelength channels.