A compact and reconfigurable silicon nitride time-bin entanglement circuit

TL;DR

This paper presents the first integrated silicon nitride photonic chip capable of generating, manipulating, and analyzing time-bin entangled photons, advancing scalable quantum communication and computation technologies.

Contribution

It introduces a reconfigurable, compact silicon nitride chip that integrates key functions for time-bin entanglement, demonstrating high-visibility interference without noise subtraction.

Findings

Achieved 88.4% two-photon interference visibility

Integrated generation, manipulation, and analysis of time-bin entanglement on a chip

Demonstrated potential for scalable quantum information processing

Abstract

Photonic chip based time-bin entanglement has attracted significant attention because of its potential for quantum communication and computation. Useful time-bin entanglement systems must be able to generate, manipulate and analyze entangled photons on a photonic chip for stable, scalable and reconfigurable operation. Here we report the first time-bin entanglement photonic chip that integrates time-bin generation, wavelength demultiplexing and entanglement analysis. A two-photon interference fringe with an 88.4% visibility is measured (without subtracting any noise), indicating the high performance of the chip. Our approach, based on a silicon nitride photonic circuit, which combines the low-loss characteristic of silica and tight integration features of silicon, paves the way for scalable real-world quantum information processors.