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

arXiv:1903.08722 · The Rochester Conferences on Coherence and Quantum Optics and the Quantum Information and Measurement meeting

Efficient parametric frequency conversions in lithium niobate nanophotonic chips

Jia‐Yang Chen, Yong Meng Sua, Zhaohui Ma, Chao Tang, Zhan Li, Yu‐Ping Huang

Published Jan 1, 2019• 3 citations
arXivHTMLPDF

Abstract

We demonstrate in a periodically-poled nanowaveguide nanowaveguide second harmonic generation with efficiency over 2200% W−1cm−2, difference frequency generation over 4.5 THz, and multichannel photon pair generation with a coincidence to accidental ratio as high as 600.
DOI
10.1364/cqo.2019.w6a.18

Related papers

Efficient parametric frequency conversion in lithium niobate nanophotonic chips

Jia‐Yang Chen, Yong Meng Sua, Zhaohui Ma +3 more

Chip-integrated nonlinear photonics holds the key for advanced optical information processing with superior performance and novel functionalities. Here, we present an optimally mode-matched, periodically poled lithium niobate nanowaveguide for efficient parametric frequency conversions on chip. Using a 4-mm nanowaveguide with subwavelength mode confinement, we demonstrate second harmonic generation with efficiency over 2200% W −1 c m −2, and broadband difference frequency generation over a 4.3-THz spectral span. These allow us to generate correlated photon pairs over multiple frequency channels via spontaneous parametric down conversion, all in their fundamental spatial modes, with a coincidence to accidental ratio as high as 600. The high efficiency and dense integrability of the present chip devices may pave a viable route to scalable nonlinear applications in both classical and quantum domains.

OSA Continuum•Oct 3, 2019•90 citations

An efficient nanophotonic source of ultra-broadband entangled photons

Usman A. Javid, Jingwei Ling, Jeremy Staffa +3 more

We demonstrate ultra-broadband spontaneous parametric down-conversion over a 100 THz bandwidth using an on-chip dispersion-engineered periodically-poled lithium niobate waveguide. The source produces photon-pairs with an unprecedented 13 GHz/mW efficiency and a coincidence-to-accidental ratio exceeding 105.

Conference on Lasers and Electro-Optics•Jan 1, 2021•0 citations

Efficient generation of broadband photon pairs in shallow-etched lithium niobate nanowaveguides

Xiao‐Xu Fang, Leiran Wang, He Lu

We design and fabricate shallow-etched periodically poled lithium niobate waveguides to realize highly efficient broadband spontaneous parametric down-conversion (SPDC) on nanophotonic chips. The shallow-etched waveguide can tolerate the non-uniformities of waveguide width induced by fabrication imperfections, enabling the generation of photon pairs with high count rate and bandwidth. We demonstrate photon-pair generation with a high brightness of 11.7 GHz/mW and bandwidth of 22 THz in a 5.7-mm-long PPLN waveguide. The generated photon pairs exhibit a strong temporal correlation with a coincidence-to-accidental ratio of up to 16262±850. Our results confirm the feasibility of shallow etching in the fabrication of an efficient SPDC device on the platform of lithium niobate on an insulator, and benefit quantum information processing with a broadband photon source.

arXiv:2406.17439•Optics Express•May 30, 2024•19 citations

Ultrabroadband Entangled Photons on a Nanophotonic Chip

Usman A. Javid, Jingwei Ling, Jeremy Staffa +3 more

The development of quantum technologies on nanophotonic platforms has seen momentous progress in the past decade. Despite that, a demonstration of time-frequency entanglement over a broad spectral width is still lacking. Here we present an efficient source of ultrabroadband entangled photon pairs on a periodically poled lithium niobate nanophotonic waveguide. Employing dispersion engineering, we demonstrate a record-high 100 THz (1.2 μm-2 μm) generation bandwidth with a high efficiency of 13 GHz/mW and excellent noise performance with the coincidence-to-accidental ratio exceeding 10^{5}. We also measure strong time-frequency entanglement with over 98% two-photon interference visibility.

arXiv:2101.04877•Physical Review Letters•Oct 27, 2021•142 citations

Efficient photon-pair generation in layer-poled lithium niobate nanophotonic waveguides

Xiaodong Shi, Sakthi Sanjeev Mohanraj, Veerendra Dhyani +7 more

Abstract Integrated photon-pair sources are crucial for scalable photonic quantum systems. Thin-film lithium niobate is a promising platform for on-chip photon-pair generation through spontaneous parametric down-conversion (SPDC). However, the device implementation faces practical challenges. Periodically poled lithium niobate (PPLN), despite enabling flexible quasi-phase matching, suffers from poor fabrication reliability and device repeatability, while conventional modal phase matching (MPM) methods yield limited efficiencies due to inadequate mode overlaps. Here, we introduce a layer-poled lithium niobate (LPLN) nanophotonic waveguide for efficient photon-pair generation. It leverages layer-wise polarity inversion through electrical poling to break spatial symmetry and significantly enhance nonlinear interactions for MPM, achieving a notable normalized second-harmonic generation (SHG) conversion efficiency of 4615% W-1 cm-2. Through a cascaded SHG and SPDC process, we demonstrate photon-pair generation with a normalized brightness of 3.1×106 Hz nm-1 mW-2 in a 3.3 mm long LPLN waveguide, surpassing existing on-chip sources under similar operating configurations. Crucially, our LPLN waveguides offer enhanced fabrication reliability and reduced sensitivity to geometric variations and temperature fluctuations compared to PPLN devices. We expect LPLN to become a promising solution for on-chip nonlinear wavelength conversion and non-classical light generation, with immediate applications in quantum communication, networking, and on-chip photonic quantum information processing.

arXiv:2405.10943•Light Science & Applications•Oct 3, 2024•69 citations

Generation of Correlated Photon Pairs in Modal Phase-Matched Lithium Niobate Nanowaveguide

Wenxiu Li, Yunru Fan, Yuanjie Yang +7 more

We demonstrate the generation of correlated photon pairs in a modal phase-matched lithium niobate nanowaveguide via cascaded second-harmonic generation (SHG) and spontaneous parametric down conversion (SPDC). A pair generation rate (PGR) of$1.1 \times 10^{5} \text{Hz} \text{mW}^{-2}$and coincidence-toaccidental ratio (CAR) up to 188 are obtained.

IEEE Optoelectronics Global Conference (OGC)•Sep 9, 2025•0 citations
Chip-integrated nonlinear photonics holds the key for advanced optical information processing with superior performance and novel functionalities. Here, we present an optimally mode-matched, periodically poled lithium niobate nanowaveguide for efficient parametric frequency conversions on chip. Using a 4-mm nanowaveguide with subwavelength mode confinement, we demonstrate second harmonic generation with efficiency over 2200% W −1 c m −2, and broadband difference frequency generation over a 4.3-THz spectral span. These allow us to generate correlated photon pairs over multiple frequency channels via spontaneous parametric down conversion, all in their fundamental spatial modes, with a coincidence to accidental ratio as high as 600. The high efficiency and dense integrability of the present chip devices may pave a viable route to scalable nonlinear applications in both classical and quantum domains.
We design and fabricate shallow-etched periodically poled lithium niobate waveguides to realize highly efficient broadband spontaneous parametric down-conversion (SPDC) on nanophotonic chips. The shallow-etched waveguide can tolerate the non-uniformities of waveguide width induced by fabrication imperfections, enabling the generation of photon pairs with high count rate and bandwidth. We demonstrate photon-pair generation with a high brightness of 11.7 GHz/mW and bandwidth of 22 THz in a 5.7-mm-long PPLN waveguide. The generated photon pairs exhibit a strong temporal correlation with a coincidence-to-accidental ratio of up to 16262±850. Our results confirm the feasibility of shallow etching in the fabrication of an efficient SPDC device on the platform of lithium niobate on an insulator, and benefit quantum information processing with a broadband photon source.
The development of quantum technologies on nanophotonic platforms has seen momentous progress in the past decade. Despite that, a demonstration of time-frequency entanglement over a broad spectral width is still lacking. Here we present an efficient source of ultrabroadband entangled photon pairs on a periodically poled lithium niobate nanophotonic waveguide. Employing dispersion engineering, we demonstrate a record-high 100 THz (1.2 μm-2 μm) generation bandwidth with a high efficiency of 13 GHz/mW and excellent noise performance with the coincidence-to-accidental ratio exceeding 10^{5}. We also measure strong time-frequency entanglement with over 98% two-photon interference visibility.
Abstract Integrated photon-pair sources are crucial for scalable photonic quantum systems. Thin-film lithium niobate is a promising platform for on-chip photon-pair generation through spontaneous parametric down-conversion (SPDC). However, the device implementation faces practical challenges. Periodically poled lithium niobate (PPLN), despite enabling flexible quasi-phase matching, suffers from poor fabrication reliability and device repeatability, while conventional modal phase matching (MPM) methods yield limited efficiencies due to inadequate mode overlaps. Here, we introduce a layer-poled lithium niobate (LPLN) nanophotonic waveguide for efficient photon-pair generation. It leverages layer-wise polarity inversion through electrical poling to break spatial symmetry and significantly enhance nonlinear interactions for MPM, achieving a notable normalized second-harmonic generation (SHG) conversion efficiency of 4615% W-1 cm-2. Through a cascaded SHG and SPDC process, we demonstrate photon-pair generation with a normalized brightness of 3.1×106 Hz nm-1 mW-2 in a 3.3 mm long LPLN waveguide, surpassing existing on-chip sources under similar operating configurations. Crucially, our LPLN waveguides offer enhanced fabrication reliability and reduced sensitivity to geometric variations and temperature fluctuations compared to PPLN devices. We expect LPLN to become a promising solution for on-chip nonlinear wavelength conversion and non-classical light generation, with immediate applications in quantum communication, networking, and on-chip photonic quantum information processing.
We demonstrate the generation of correlated photon pairs in a modal phase-matched lithium niobate nanowaveguide via cascaded second-harmonic generation (SHG) and spontaneous parametric down conversion (SPDC). A pair generation rate (PGR) of1.1×105HzmW−21.1 \times 10^{5} \text{Hz} \text{mW}^{-2}1.1×105HzmW−2and coincidence-toaccidental ratio (CAR) up to 188 are obtained.