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

Physical Review Applied

Silicon Photonic Wires for Broadband Polarization Entanglement at Telecommunication Wavelengths

Shivani Sharma, Vivek Venkataraman, Joyee Ghosh

Published Oct 18, 2022• 12 citations
Publisher

Abstract

Compact and scalable sources of broadband polarization entanglement at telecommunication wavelengths will pave the way for multiuser long-distance quantum communication at enhanced data rates, but progress toward this goal has been hindered due to large birefringence in conventional silicon-on-insulator nanowaveguides. The authors theoretically demonstrate, via dispersion engineering, the successful generation of polarization-entangled photon pairs over a broad range of wavelengths. This work also provides a strategy to avoid entanglement degradation due to polarization-mode dispersion. The proposed devices will be useful building blocks for large-scale quantum communication networks.

DOI
10.1103/physrevapplied.18.044043

Related papers

Entanglement Generation Using Silicon Photonic Wire Waveguide

Hiroki Takesue, K. Harada, Hiroshi Fukuda +5 more

This paper reviews recent progress on telecom-band entangled photon-pair sources based on spontaneous four-wave mixing (SFWM) in a silicon photonic wire waveguide. Thanks to the large third order nonlinearity of nano-scale silicon waveguides, we can generate photon pairs efficiently. Moreover, the use of silicon waveguides enable us to avoid the noise photons caused by spontaneous Raman scattering, which has been a serious problem with entanglement sources based on SFWM in dispersion shifted fiber. We successfully demonstrated high-purity time-bin and polarization entanglement generation using 1-cm long silicon waveguides.

Journal of Nanoscience and Nanotechnology•Mar 1, 2010•1 citation

Telecom-Band Quantum Light Sources Using Dispersion-Engineered SOI Waveguides

Shivani Sharma, Vivek Venkataraman, Joyee Ghosh

We theoretically demonstrate the generation of spectrally pure (purity ~ 95%) heralded single photons, and also broadband (~60-nm around 1550-nm) polarization-entangled photon pairs (concurrence>0.96), at telecom wavelengths via extensive dispersion engineering in silicon nano-waveguides.

Optica Advanced Photonics Congress•Jan 1, 2022•1 citation

Silicon-on-insulator integrated source of polarization-entangled photons

Laurent Olislager, Jassem Safioui, Stéphane Clemmen +5 more

We report the experimental generation of polarization-entangled photons at telecommunication wavelengths using spontaneous four-wave mixing in silicon-on-insulator wire waveguides. The key component is a 2D coupler that transforms path entanglement into polarization entanglement at the output of the device. Using quantum state tomography we find that the produced state has fidelity 88% with a pure nonmaximally entangled state. The produced state violates the CHSH Bell inequality by S=2.37 ± 0.19.

arXiv:1304.0642•Optics Letters•May 28, 2013•63 citations

Entanglement distribution over metropolitan fiber using an on-chip broadband polarization-entangled photon source

Zi-Heng Jiang, Yikai Chen, Wenhan Yan +10 more

Entangled photon pairs are of crucial importance in quantum networks. For the future demands of large-scale and secure quantum communication, integrated photon sources are highly effective solutions. Here, we report entanglement distribution over 30 km in a metropolitan area using an on-chip broadband silicon nanowire biphoton polarization-entangled source based on a silicon-on-insulator platform. This source generates a continuous spectrum spanning the entire C band (4.5 THz), achieving locally detected coincidence counts of about 154 kHz within a 100-GHz bandwidth, making it suitable for long-distance entanglement distribution among multiple users. By combining this source with quantum entanglement, enhanced by high-precision clock synchronization that achieves a standard deviation of 56.8 ps over 600 s, we observe a violation of the Clauser-Horne-Shimony-Holt inequality by 27.8 standard deviations. Our results showcase the potential of silicon photonic technology as a scalable and practical platform for quantum technologies.

arXiv:2503.07198•Physical Review Applied•Sep 16, 2025•7 citations

Ultra-broadband spectral and polarisation entanglement using dispersion-engineered nanophotonic waveguides

Mahmoud Almassri, Mohammed F. Saleh

In this paper, we propose exploiting dispersion-engineered nanophotonic waveguides in generating unprecedented ultra-broadband spectral and polarisation entanglement using spontaneous four-wave mixing parametric processes. We developed a simplified theoretical quantum framework to investigate and analyze these interactions under pulse source excitations. Using aluminum gallium arsenide and thin-film lithium niobate waveguides, we anticipate obtaining photon pairs with high-dimensional frequency entanglement, characterized by Schmidt numbers as large as 10 8 , and covering the wavelength range 940–2730 nm (equivalent to a 210 THz bandwidth). Additionally, we show that Al 0.3 Ga 0.7 As waveguides with hybrid cladding can enable the generation of polarisation-entangled photon pairs with concurrence exceeding 0.93 across wavelengths from 1175 nm to 1750 nm, spanning almost across all the telecommunication bands with only approximately 27 nm window inevitable-degradation around the pump wavelength. We envisage that these introduced integrated on-chip sources will significantly advance quantum photonic technologies, enabling breakthroughs in multi-channel quantum networking and scalable quantum information systems.

arXiv:2506.17819•Optics Express•Jun 25, 2025•1 citation

Experimental entanglement generation for quantum key distribution beyond 1 Gbit/s

Sebastian Philipp Neumann, Mirela Selimović, Martin Bohmann +1 more

Top-performance sources of photonic entanglement are an indispensable resource for many applications in quantum communication, most notably quantum key distribution. However, up to now, no source has been shown to simultaneously exhibit the high pair-creation rate, broad bandwidth, excellent state fidelity, and low intrinsic loss necessary for gigabit secure key rates. In this work, we present for the first time a source of polarization-entangled photon pairs at telecommunication wavelengths that covers all these needs of real-world quantum-cryptographic applications, thus enabling unprecedented quantum-secure key rates of more than 1 Gbit/s. Our source is designed to optimally exploit state-of-the-art telecommunication equipment and detection systems. Any technological improvement of the latter would result in an even higher rate without modification of the source. We discuss the used wavelength-multiplexing approach, including its potential for multi-user quantum networks and its fundamental limitations. Our source paves the way for high-speed quantum encryption approaching present-day internet bandwidth.

arXiv:2107.07756•Quantum•Sep 29, 2022•33 citations
Compact and scalable sources of broadband polarization entanglement at telecommunication wavelengths will pave the way for multiuser long-distance quantum communication at enhanced data rates, but progress toward this goal has been hindered due to large birefringence in conventional silicon-on-insulator nanowaveguides. The authors theoretically demonstrate, via dispersion engineering, the successful generation of polarization-entangled photon pairs over a broad range of wavelengths. This work also provides a strategy to avoid entanglement degradation due to polarization-mode dispersion. The proposed devices will be useful building blocks for large-scale quantum communication networks.
This paper reviews recent progress on telecom-band entangled photon-pair sources based on spontaneous four-wave mixing (SFWM) in a silicon photonic wire waveguide. Thanks to the large third order nonlinearity of nano-scale silicon waveguides, we can generate photon pairs efficiently. Moreover, the use of silicon waveguides enable us to avoid the noise photons caused by spontaneous Raman scattering, which has been a serious problem with entanglement sources based on SFWM in dispersion shifted fiber. We successfully demonstrated high-purity time-bin and polarization entanglement generation using 1-cm long silicon waveguides.
We report the experimental generation of polarization-entangled photons at telecommunication wavelengths using spontaneous four-wave mixing in silicon-on-insulator wire waveguides. The key component is a 2D coupler that transforms path entanglement into polarization entanglement at the output of the device. Using quantum state tomography we find that the produced state has fidelity 88% with a pure nonmaximally entangled state. The produced state violates the CHSH Bell inequality by S=2.37 ± 0.19.
Entangled photon pairs are of crucial importance in quantum networks. For the future demands of large-scale and secure quantum communication, integrated photon sources are highly effective solutions. Here, we report entanglement distribution over 30 km in a metropolitan area using an on-chip broadband silicon nanowire biphoton polarization-entangled source based on a silicon-on-insulator platform. This source generates a continuous spectrum spanning the entire C band (4.5 THz), achieving locally detected coincidence counts of about 154 kHz within a 100-GHz bandwidth, making it suitable for long-distance entanglement distribution among multiple users. By combining this source with quantum entanglement, enhanced by high-precision clock synchronization that achieves a standard deviation of 56.8 ps over 600 s, we observe a violation of the Clauser-Horne-Shimony-Holt inequality by 27.8 standard deviations. Our results showcase the potential of silicon photonic technology as a scalable and practical platform for quantum technologies.
In this paper, we propose exploiting dispersion-engineered nanophotonic waveguides in generating unprecedented ultra-broadband spectral and polarisation entanglement using spontaneous four-wave mixing parametric processes. We developed a simplified theoretical quantum framework to investigate and analyze these interactions under pulse source excitations. Using aluminum gallium arsenide and thin-film lithium niobate waveguides, we anticipate obtaining photon pairs with high-dimensional frequency entanglement, characterized by Schmidt numbers as large as 10 8 , and covering the wavelength range 940–2730 nm (equivalent to a 210 THz bandwidth). Additionally, we show that Al 0.3 Ga 0.7 As waveguides with hybrid cladding can enable the generation of polarisation-entangled photon pairs with concurrence exceeding 0.93 across wavelengths from 1175 nm to 1750 nm, spanning almost across all the telecommunication bands with only approximately 27 nm window inevitable-degradation around the pump wavelength. We envisage that these introduced integrated on-chip sources will significantly advance quantum photonic technologies, enabling breakthroughs in multi-channel quantum networking and scalable quantum information systems.
Top-performance sources of photonic entanglement are an indispensable resource for many applications in quantum communication, most notably quantum key distribution. However, up to now, no source has been shown to simultaneously exhibit the high pair-creation rate, broad bandwidth, excellent state fidelity, and low intrinsic loss necessary for gigabit secure key rates. In this work, we present for the first time a source of polarization-entangled photon pairs at telecommunication wavelengths that covers all these needs of real-world quantum-cryptographic applications, thus enabling unprecedented quantum-secure key rates of more than 1 Gbit/s. Our source is designed to optimally exploit state-of-the-art telecommunication equipment and detection systems. Any technological improvement of the latter would result in an even higher rate without modification of the source. We discuss the used wavelength-multiplexing approach, including its potential for multi-user quantum networks and its fundamental limitations. Our source paves the way for high-speed quantum encryption approaching present-day internet bandwidth.