Ultrafast quantum key distribution using fully parallelized quantum channels

TL;DR

This paper presents a multichannel quantum key distribution system utilizing parallelized quantum channels, superconducting nanowire detectors, and FPGA control to enable high-bandwidth secure communication at telecom wavelengths.

Contribution

The authors developed a plug-and-play multichannel QKD system with high secret key rates, integrating superconducting detectors and parallelized photon counting for efficient quantum communication.

Findings

Achieved high secret key rates with multichannel QKD.

Demonstrated continuous operation at telecom wavelengths.

Integrated superconducting detectors with FPGA-controlled setup.

Abstract

The field of quantum information processing offers secure communication protected by the laws of quantum mechanics and is on the verge of finding wider application for information transfer of sensitive data. To overcome the obstacle of inadequate cost-efficiency, extensive research is being done on the many components required for high data throughput using quantum key distribution (QKD). Aiming for an application-oriented solution, we report on the realization of a multichannel QKD system for plug-and-play high-bandwidth secure communication at telecom wavelength. For this purpose, a rack-sized multichannel superconducting nanowire single photon detector (SNSPD) system, as well as a highly parallelized time-correlated single photon counting (TCSPC) unit have been developed and linked to an FPGA-controlled QKD evaluation setup allowing for continuous operation and achieving high secret key rates using a coherent-one-way protocol.