Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Hyperentangled photon pairs emitted from an integrated source delivering more than 1 Gpair/s

Linda Gianini, Andrea Barone, Marcello Bacchi, Jonathan Faugier-Tovar, Sara Congia, Massimo Borghi, Noemi Tagliavacche, Luca Zatti, Quentin Wilmart, S. Olivier, Marco Liscidini, Mattéo Galli, Daniele Bajoni

Published Jan 1, 2024• 0 citations
Publisher

Abstract

We demonstrate a high-rate source of hyperentangled photons based on a silicon racetrack resonator. Hyperentanglement is verified by violating Bell’s inequality in both time and frequency domains, and obtaining a high-purity state using frequency-bin encoding.
DOI
10.1364/cleo_fs.2024.ff2k.4

Related papers

Generation of hyperentangled photon pairs in the time and frequency domain on a silicon photonic chip

Sara Congia, Massimo Borghi, Emanuele Brusaschi +11 more

Multi-dimensional entangled photon states represent an important resource in quantum communication networks. Specifically, hyperentangled states presenting simultaneous entanglement in several degrees of freedom (DoF) stand out for their noise resilience and information capacity. In this work, we demonstrate the generation of hyperentangled photon pairs in the time and frequency-bin domain by spontaneous four-wave mixing from the coherent driving of two integrated silicon microresonators. We demonstrate entanglement in each DoF by proving the violation of the Clauser-Horne-Shimony-Holt (CHSH) inequality by more than 27 standard deviations (STDs) in each reduced space. Genuine hyperentanglement is then assessed from the negativity of a hyperentanglement witness, which is verified by more than 60 STDs. These results mark the first, to the best of our knowledge, demonstration of time-frequency bin hyperentanglement in an integrated silicon photonic device.

arXiv:2506.19110•Optics Letters•Jul 3, 2025•5 citations

A silicon integrated source of hyper-entangled photon pairs with rate exceeding 1 billion pairs per second

Linda Gianini, Andrea Barone, Marcello Bacchi +9 more

Abstract Optical losses and environmental noise present significant challenges for the coherent propagation of entangled states of light over large distances in quantum communication protocols. To cope with optical losses, one possible strategy is to increase the emission rate as much as possible. Decoherence, related to thermal and pressure fluctuation and to the presence of parasitic processes, can be overcome by encoding information via hyper-entanglement, i.e. entanglement over multiple degrees of freedom (DoFs). In this work we experimentally demonstrate a silicon-integrated device implementing both strategies, demonstrating the emission of spectrally multiplexed and hyper-entangled photon pairs. The pair generation rate exceeds 10 9 pairs per second at the output of the device over an 8 THz-wide comb of multiplexed frequency modes. Hyperentanglement is proved by showing entanglement in the frequency-bin and time-energy DoFs, along with high purity of the states when tracing over the time-energy degree of freedom. Quantum state tomography shows both fidelity and purity to be greater than 95% in the frequency domain, while, in the time-domain encoding, Bell’s inequality is violated by more than 10 standard deviations.

npj Nanophotonics•Jan 7, 2026•6 citations

Microstructure-fiber-based source of high-flux hyperentangled photon-pairs

Jun Chen, Jingyun Fan, Matthew D. Eisaman +1 more

We generate hyperentangled (time-bin and polarization) photon-pairs using a microstructure-fiber Sagnac interferometer. Two-photon interference visibilities in both degrees of freedom are > 84%, and Bellpsilas inequality is violated by 27 sigma at 1-kHz coincidence rate.

Conference on Lasers and Electro-Optics•May 4, 2008•0 citations

High-Flux Hyperentangled Photon-Pairs From a Microstructure-Fiber Sagnac Interferometer

Jun Chen, Jingyun Fan, Matthew D. Eisaman +1 more

We generate hyperentangled (time-bin and polarization) photon-pairs using a microstructure-fiber Sagnac interferometer. Two-photon-interference visibilities in both degrees of freedom are >83%, and the Bell’s inequality is violated by 25 σ at a 1-kHz coincidence rate.

SPIE eBooks•Sep 16, 2007•0 citations

High-Flux Hyperentangled Photon-Pairs from a Microstructure-Fiber Sagnac Interferometer

Jun Chen, Jingyun Fan, Matthew D. Eisaman +1 more

We generate hyperentangled (time-bin and polarization) photon-pairs using a microstructure-fiber Sagnac interferometer. Two-photon-interference visibilities in both degrees of freedom are >83%, and the Bell’s inequality is violated by 25 σ at a 1-kHz coincidence rate.

Frontiers in Optics•Jan 1, 2007•0 citations

Generation of hyperentangled photon pairs encoded in the time-bin and frequency-bin degree of freedom from silicon microrings

Sara Congia, Massimo Borghi, Emanuele Brusaschi +5 more

Multidimensional entangled photon states represent a useful resource for large-scale quantum communication networks. Among them, hyperentangled (HE) states, i.e. presenting simultaneous entanglement in several degrees of freedom (DoFs), stand out for their noise resilience. In this work, we demonstrate the generation of HE photon pairs in the time-bin and the frequency-bin DoFs through Spontaneous Four-Wave Mixing (SFWM) from two silicon-on-insulator high-brightness microring resonators.

International Conference on Transparent Optical Networks•Jul 6, 2025•0 citations
Multi-dimensional entangled photon states represent an important resource in quantum communication networks. Specifically, hyperentangled states presenting simultaneous entanglement in several degrees of freedom (DoF) stand out for their noise resilience and information capacity. In this work, we demonstrate the generation of hyperentangled photon pairs in the time and frequency-bin domain by spontaneous four-wave mixing from the coherent driving of two integrated silicon microresonators. We demonstrate entanglement in each DoF by proving the violation of the Clauser-Horne-Shimony-Holt (CHSH) inequality by more than 27 standard deviations (STDs) in each reduced space. Genuine hyperentanglement is then assessed from the negativity of a hyperentanglement witness, which is verified by more than 60 STDs. These results mark the first, to the best of our knowledge, demonstration of time-frequency bin hyperentanglement in an integrated silicon photonic device.
Abstract Optical losses and environmental noise present significant challenges for the coherent propagation of entangled states of light over large distances in quantum communication protocols. To cope with optical losses, one possible strategy is to increase the emission rate as much as possible. Decoherence, related to thermal and pressure fluctuation and to the presence of parasitic processes, can be overcome by encoding information via hyper-entanglement, i.e. entanglement over multiple degrees of freedom (DoFs). In this work we experimentally demonstrate a silicon-integrated device implementing both strategies, demonstrating the emission of spectrally multiplexed and hyper-entangled photon pairs. The pair generation rate exceeds 10 9 pairs per second at the output of the device over an 8 THz-wide comb of multiplexed frequency modes. Hyperentanglement is proved by showing entanglement in the frequency-bin and time-energy DoFs, along with high purity of the states when tracing over the time-energy degree of freedom. Quantum state tomography shows both fidelity and purity to be greater than 95% in the frequency domain, while, in the time-domain encoding, Bell’s inequality is violated by more than 10 standard deviations.