Decoy-state quantum key distribution over 227 km with a frequency-converted telecom single-photon source

Abstract

We implement a decoy-state quantum key distribution scheme using a telecom C-band single-emitter source. The decoy states are created by varying the optical excitation of the quantum emitter to modulate the photon number distribution. We provide an analysis of our scheme based on existing security proofs, allowing the calculation of secret key rates including finite key effects. This enables us to demonstrate, with a realistic single-photon source, positive secret key rates using our scheme over 227 km of optical fiber, equivalent to a loss tolerance one order of magnitude greater than non-decoy schemes. This work broadens the scope of single-photon sources in future quantum networks by enabling long-distance QKD with realistic levels of single-photon purity.

References in corpus (19)

• The Quantum Internet
• QuTiP 2: A Python framework for the dynamics of open quantum systems
• Provably Secure and Practical Quantum Key Distribution over 307 km of Optical Fibre
• Experimental Twin-Field Quantum Key Distribution Over 1000 km Fiber Distance
• High-rate quantum key distribution exceeding 110 Mb/s
• Quantum Communication Using Semiconductor Quantum Dots
• Quantum dots for photonic quantum information technology
• Fast Single Photon Detectors and real-time Key Distillation: Enabling High Secret Key Rate QKD Systems
• Discrete-phase-randomized coherent state source and its application in quantum key distribution
• Signatures of two-photon pulses from a quantum two-level system
• Photon statistics from a resonantly driven quantum dot
• High-rate intercity quantum key distribution with a semiconductor single-photon source
• Single-emitter quantum key distribution over 175 km of fiber with optimised finite key rates
• A Bright Source of Telecom Single Photons Based on Quantum Frequency Conversion
• High Purcell-enhancement in quantum-dot hybrid circular Bragg grating cavities for GHz-clockrate generation of indistinguishable photons
• Controlling the Photon Number Coherence of Solid-state Quantum Light Sources for Quantum Cryptography
• Security bounds for decoy-state QKD with arbitrary photon-number statistics
• Realization of an untrusted intermediate relay architecture using a quantum dot single-photon source
• Secure Quantum Key Distribution Using a Room-Temperature Quantum Emitter