# Fast Single Photon Detectors and real-time Key Distillation: Enabling High Secret Key Rate QKD Systems

**Authors:** Fadri Grünenfelder, Alberto Boaron, Matthieu Perrenoud, Giovanni V. Resta, Davide Rusca, Claudio Barreiro, Raphaël Houlmann, Rebecka Sax, Lorenzo Stasi, Sylvain El-Khoury, Esther Hänggi, Nico Bosshard, Félix Bussières, Hugo Zbinden  
**arXiv:** [2210.16126](https://arxiv.org/abs/2210.16126)  
**Date:** 2022-10-28  
**Summary page:** https://www.summarizepaper.com/en/paper/2210.16126v1/

## Abstract

Quantum Key Distribution has made continuous progress over the last 20 years and is now commercially available. However, the secret key rates (SKR) are still limited to a few Mbps. Here, we present a custom multipixel superconducting nanowire single-photon detectors and fast acquisition and real-time key distillation electronics, removing two roadblocks and allowing an increase of the SKR of more than an order of magnitude. In combination with a simple 2.5 GHz clocked time-bin quantum key distribution system, we can generate secret keys at a rate of 64 Mbps over a distance of 10.0 km and at a rate of 3.0 Mbps over a distance of 102.4 km with real-time key distillation.