Gigahertz-rate thin-film lithium niobate receiver for time-bin quantum communication

Andrea Bernardi; Marco Clementi; Marcello Bacchi; Matías Rubén Bolaños; Sara Congia; Francesco Garrisi; Andrea Martellosio; Marco Passoni; Alexander Wrobel; Costantino Agnesi; Giuseppe Vallone; Paolo Villoresi; Federico Andrea Sabattoli; Matteo Galli; Daniele Bajoni

doi:10.1038/s41377-026-02306-5

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Gigahertz-rate thin-film lithium niobate receiver for time-bin quantum communication

Original Articles

- Gigahertz-rate thin-film lithium niobate receiver for time-bin quantum communication
- Light: Science & Applications Vol. 15, Issue 8, Pages: 2650-2666(2026)
- Affiliations：
  
  1.Dipartimento di Ingegneria Industriale e dell'Informazione, Università di Pavia, Via A. Ferrata 5, 27100 Pavia, Italy
  2.Advanced Fiber Resources Milan s.r.l., Via Fellini 4, 20097 San Donato Milanese, Italy
  3.Dipartimento di Fisica "A. Volta", Università di Pavia, Via A. Bassi 6, 27100 Pavia, Italy
  4.Dipartimento di Ingegneria dell'Informazione, Università degli Studi di Padova, Via Gradenigo 6B, 35131 Padua, Italy
  5.CEA LETI and University Grenoble Alpes, MINATEC Campus, F-38054 Grenoble Cedex, France
  6.Quantum Technologies Research Center, Università degli Studi di Padova, Via Gradenigo 6B, 35131 Padua, Italy
- Author bio：
  
  Andrea Bernardi (andrea.bernardi01@universitadipavia.it)
- Funds：
- DOI：10.1038/s41377-026-02306-5
  CLC：
- Received：10 October 2025，
  
  Revised：2026-03-25，
  
  Accepted：09 April 2026，
  
  Online First：18 May 2026，
  
  Published：31 August 2026
- Accepted：
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Bernardi, A. et al. Gigahertz-rate thin-film lithium niobate receiver for time-bin quantum communication. Light: Science & Applications, 15, 2650-2666 (2026).
DOI：

Bernardi, A. et al. Gigahertz-rate thin-film lithium niobate receiver for time-bin quantum communication. Light: Science & Applications, 15, 2650-2666 (2026). DOI： 10.1038/s41377-026-02306-5.

摘要

Abstract

Time-bin encoded quantum states of light are crucial for quantum technology applications. The integration of manipulation functionalities into chip-scale devices is essential for deploying scalable

high-performace

and cost-effective quantum networks. Here we develop a fully integrated

high-throughput quantum receiver based on the thin-film lithium niobate (TFLN) platform

capable of high-speed electro-optic manipulation of time-bin encoded quantum states. The device's novel architecture enables active switching of time-bin quantum states with an electro-optic bandwidth exceeding 30 GHz

while supporting real-time arbitrary projective measurements with a bandwidth of over 1 GHz. We showcase its versatility and performance through several applications

including the certification of entanglement with Bell's inequality violation by 38 standard deviations and with > 95% visibility. We then apply it to a fiber-based quantum communication scenario

where we experimentally demonstrate an entanglement-based quantum key distribution (QKD) protocol

achieving stable finite-size secure key rates exceeding 25 kbit/s over 12 h of continuous operation. By leveraging a high-speed active switching scheme

the system overcomes the need for temporal post-selection

eliminating a fundamental loophole that compromises the security of time-bin entanglement-based QKD protocols and relaxes the temporal resolution requirements of single-photon detectors. Moreover

it enables active selection of the projection basis

increasing the flexibility for communication parties. This approach establishes a versatile and scalable architecture for time-bin encoded quantum communication

enabling practical protocols on industry-grade photonic technology.

关键词

Keywords

references

Schrödinger, E. Probability relations between separated systems. Math. Proc. Camb. Philos. Soc. 32 , 446–452 (1936)..

Nielsen, M. A. & Chuang, I. L. Quantum Computation and Quantum Information (Cambridge Univ. Press, Cambridge, 2010).

Pittaluga, M. et al. Long-distance coherent quantum communications in deployed telecom networks. Nature 640 , 911–917 (2025)..

Ekert, A. K. et al. Practical quantum cryptography based on two-photon interferometry. Phys. Rev. Lett. 69 , 1293–1295 (1992)..

Bennett, C. H., Brassard, G. & Mermin, N. D. Qua ntum cryptography without Bell's theorem. Phys. Rev. Lett. 68 , 557–559 (1992)..

Bennett, C. H. & Brassard, G. Quantum cryptography: public key distribution and coin tossing. Theor. Comput. Sci. 560 , 7–11 (2014)..

Lo, H. K., Curty, M. & Tamaki, K. Secure quantum key distribution. Nat. Photon. 8 , 595–604 (2014)..

Ma, X. F., Fung, C. H. F. & Lo, H. K. Quantum key distribution with entangled photon sources. Phys. Rev. A 76 , 012307 (2007)..

Franson, J. D. Bell inequality for position and time. Phys. Rev. Lett. 62 , 2205–2208 (1989)..

Tittel, W. et al. Violation of bell inequalities by photons more than 10 km apart. Phys. Rev. Lett. 81 , 3563–3566 (1998)..

Brendel, J. et al. Pulsed energy-time entangled twin-photon source for quantum communication. Phys. Rev. Lett. 82 , 2594–2597 (1999)..

Marcikic, I. et al. Time-bin entangled qubits for quantum comm unication created by femtosecond pulses. Phys. Rev. A 66 , 062308 (2002)..

Montaut, N. et al. Progress in integrated and fiber optics for time-bin based quantum information processing. Adv. Opt. Technol. 14 , 1560084 (2025)..

Singh, A. et al. Photonic quantum information with time-bins: principles and applications. Preprint at https://arxiv.org/abs/2507.08102 https://arxiv.org/abs/2507.08102 (2025).

Yu, H. et al. Quantum key distribution implemented with d-level time-bin entangled photons. Nat. Commun. 16 , 171 (2025)..

Chapman, J. C., Lim, C. C. W. & Kwiat, P. G. Hyperentangled time-bin and polarization quantum key distribution. Phys. Rev. Appl. 18 , 044027 (2022)..

Congia,S. et al. Generation of hyperentangled photon pairs in the time and frequency domain on a silicon photonic chip. Opt. Lett. 50 , 5117 (2025)..

Patel, K. A. et al. Coexistence of high-bit-rate quantum key distribution and data on optical fiber. Phys. Rev. X 2 , 041010 (2012)..

Zhang, Q. et al. Generation of 10-GHz clock sequential time-bin entanglement. Opt. Express 16 , 3293–3298 (2008)..

Mueller, A. et al. High-rate multiplexed entanglement source based on time-bin qubits for advanced quantum networks. Opt. Quantum 2 , 64–71 (2024)..

Fitzke, E. et al. Scalable network for simultaneous pairwise quantum key distribution via entanglement-based time-bin coding. PRX Quantum 3 , 020341 (2022)..

Kim, J. H. et al. Quantum communication with time-bin entanglement over a wavelength-multiplexed fiber network. APL Photon. 7 , 016106 (2022)..

Huang, Y. W. et al. A sixteen-user time-bin entangled quantum communication network with fully connected topology. Laser Photon. Rev. 19 , 2301026 (2025)..

Finco, G. et al. Time-bin entangled bell state generation and tomography on thin-film lithium niobate. npj Quantum Inf. 10 , 135 (2024)..

Maeder, A. et al. Programm able bell state generation in an integrated thin film lithium niobate circuit. Light Sci. Appl. 15 , 43 (2026)..

Aerts, S. et al. Two-photon Franson-type experiments and local realism. Phys. Rev. Lett. 83 , 2872–2875 (1999)..

Jogenfors, J. et al. Hacking the Bell test using classical light in energy-time entanglement–based quantum key distribution. Sci. Adv. 1 , e1500793 (2015)..

Xavier, G. B. et al. Energy-time and time-bin entanglement: past, present and future. npj Quantum Inf. 11 , 129 (2025)..

Vedovato, F. et al. Postselection-loophole-free Bell violation with genuine time-bin entanglement. Phys. Rev. Lett. 121 , 190401 (2018)..

Verstraete, F. & Wolf, M. M. Entanglement versus Bell violations and their behavior under local filtering operations. Phys. Rev. Lett. 89 , 170401 (2002)..

Clauser, J. F. et al. Proposed experiment to test local hidden-variable theories. Phys. Rev. Lett. 23 , 880–884 (1969)..

Takesue, H. et al. Entanglement generation using silicon wire waveguide. Appl. Phys. Lett. 91 , 201108 (2007)..

Altepeter, J. B., Jeffrey, E. R. & Kwiat, P. G. Photonic state tomography. Adv. At. Mol. Opt. Phys. 52 , 105–159 (2005)..

Kuzucu, O. et al. Joint temporal density measurements for two-photon state characterization. Phys. Rev. Lett. 101 , 153602 (2008)..

Drago, C. & Sipe, J. E. Deconstructing squeezed light: Schmidt decomposition versus the whittaker-shannon interpolation. Phys. Rev. A 110 , 023710 (2024)..

Borghi, M. et al. Uncorrelated photon pair generation from an integrated silicon nitride resonator measured by time-resolved coincidence detection. Opt. Lett. 49 , 3966 (2024)..

Wootters, W. K. Entanglement of formation of an arbitrary state of two qubits. Phys. Rev. Lett. 80 , 2245–2248 (1998)..

Gisin, N. et al. Quantum cryptography. Rev. Mod. Phys. 74 , 145–195 (2002)..

Lo, H.-K., Chau, H. F. & Ardehali, M. Efficient quantum key distribution scheme and a proof of its unconditional security. J. Cryptol. 18 , 133–165 (2005)..

Tomamichel, M. et al. Tight finite-key analysis for quantum cryptography. Nat. Commun. 3 , 634 (2012)..

Mannalath, V., Zapatero, V. & Curty, M. Sharp finite statistics for quantum key distribution. Phys. Rev. Lett. 135 , 020803 (2025)..

Pelet, Y. et al. Entanglement-based clock syntonization for quantum key distribution networks: demonstration over a 50 km-long link. Appl. Phys. Lett. 126 , 174003 (2025)..

Williams, J. et al. Implementation of quantum key distribution and quantum clock synchronization via time bin encoding. In Proc. SPIE 11699, Quantum Computing, Communication, and Simulation 16–25 (SPIE, 2021).

Calderaro, L. et al. Fast and simple qubit-based synchronization for quantum key distribution. Phys. Rev. Appl. 13 , 054041 (2020)..

Acín, A. et al. Device-independent security of quantum cryptography against collective attacks. Phys. Rev. Lett. 98 , 230501 (2007)..

Peri, A. et al. High-performance heterodyne receiver for quantum information processing in a laser-written integrated photonic platform. Adv. Photon. 8 , 016009–016009 (2026)..

Bertapelle, T. et al. High-speed source-device-independent quantum random number generator on a chip. Opt. Quantum 3 , 111–118 (2025)..

Santagiustina, F. B. L. et al. Experimental post-selection loophole-free time-bin and energy-time nonlocality with integrated photonics. Optica 11 , 498–511 (2024)..

Marcikic, I. et al. Distribution of time-bin entangled qubits over 50 km of optical fiber. Phys. Rev. Lett. 93 , 180502 (2004)..

Honjo, T. et al. Long-distance entanglement-based quantum key distribution over optical fiber. Opt. Express 16 , 19118–19126 (2008)..

Pelet, Y. et al. Operational entanglement-based quantum key distribution over 50 km of field-deployed optical fibers. Phys. Rev. Appl. 20 , 044006 (2023)..

de Riedmatten, H. et al. Long-distance entanglement swapping with photons from separated sources. Phys. Rev. A 71 , 050302 (2005)..

Tagliavacche, N. et al. Frequency-bin entanglement-based quantum key distribution. npj Quantum Inf. 11 , 60 (2025)..

Zhang, J. et al. Compact polarization splitter-rotator based on lithium niobate-on-insulator platform. J. Appl. Phys. 136 , 164503 (2024)..

Sheng, Y.-B., Zhou, L. & Long, G.-L. One-step quantum secure direct communication. Sci. Bull. 67 , 367–374 (2022)..

Yang, Y. L. et al. A 300-km fully-connected quantum secure direct communication network. Sci. Bull. 70 , 1445–1451 (2025)..

Sheng, Y.-B. & Deng, F.-G. Deterministic entanglement purification and complete nonlocal Bell-state analysis with hyperentanglement. Phys. Rev. A 81 , 032307 (2010)..

Korzh, B. et al. Demonstration of sub-3 ps temporal r esolution with a superconducting nanowire single-photon detector. Nat. Photon. 14 , 250–255 (2020)..

Jiang, X. H., Wu, H. & Dai, D. X. Low-loss and low-crosstalk multimode waveguide bend on silicon. Opt. express 26 , 17680–17689 (2018)..

Wang, C. L. et al. Lithium tantalate photonic integrated circuits for volume manufacturing. Nature 629 , 784–790 (2024)..

Ekert, A. K. Quantum cryptography based on Bell's theorem. Phys. Rev. Lett. 67 , 661–663 (1991)..

Zhuang, S.-C. et al. Ultrabright entanglement based quantum key distribution over a 404 km optical fiber. Phys. Rev. Lett. 134 , 230801 (2025)..

Lim, C. C. W. et al. Security analysis of quantum key distribution with small block length and its application to quantum space communications. Phys. Rev. Lett. 126 , 100501 (2021)..

Zhong, Z.-Q. et al. Hyperentanglement quantum communication over a 50 km noisy fiber channel. Optica 11 , 1056–1061 (2024)..

Doda,M. et al. Quantum key distribution overcoming extreme noise: Simultaneous subspace coding using high-dimensional entanglement. Phys. Rev. Appl. 15 , 034003 (2021)..

Neumann, S. P. et al. Continuous entanglement distribution over a transnational 248 km fiber link. Nat. Commun. 13 , 6134 (2022)..

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