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Scalable Optical Quantum State Synthesizer with Dual-Mode Resonator Memory

Fumiya Hanamura1, Kan Takase1,2,3, Kazuki Hirota1, Rajveer Nehra1,4,5, Florian Lang6, Shigehito Miki7, Hirotaka Terai7, Masahiro Yabuno7, Takahiro Kashiwazaki8 et al.

Asuka Inoue8, Takeshi Umeki8, Warit Asavanant1,2,3, Mamoru Endo1,2, Jun-ichi Yoshikawa2, and Akira Furusawa1,2,3,*

  • *Contact author: akiraf@ap.t.u-tokyo.ac.jp
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PRX Quantum 6, 040336 – Published 14 November, 2025

DOI: https://doi.org/10.1103/ztqs-q4ql

Abstract

Optical quantum computing is a promising approach for achieving large-scale quantum computation. While Gaussian operations have been successfully scaled, the inherently weak nonlinearity in optics makes generating highly non-Gaussian states a critical challenge for universality and fault tolerance. Here, we propose and experimentally demonstrate a scalable method to generate optical non-Gaussian states with a resonator-based quantum memory that supports continuous-time storage and retrieval, in contrast to conventional loop-based memories. We introduce a dual-mode operation of the memory, enabling both storage and entangling functionalities within a single device. By employing a time-domain-multiplexed approach, we successfully demonstrate both cat and Gottesman-Kitaev-Preskill breeding protocols in a scalable fashion, marking a key step toward quantum error correction. Our experiment also marks the first full demonstration of an optical resonator memory performing writing, storage, and readout operations. We validate the memory by storing squeezed single-photon states with up to 93% total efficiency, and measure an energy relaxation time T1=2.3μs and dephasing time Tϕ=0.96μs. These results establish a scalable pathway to generating complex non-Gaussian states required for fault-tolerant optical quantum computing. Beyond computation, our techniques provide new tools for enhancing quantum communication, sensing, and metrology.

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Popular Summary

Photons are attractive carriers of quantum information, but fully unlocking their potential requires the ability to generate non-Gaussian states, essential resources for universal quantum computing and error correction. Existing approaches rely on many probabilistic sources operating in parallel, which limits scalability.

We demonstrate a new method based on a resonator quantum memory that can both store quantum states and entangle them with incoming light. This dual functionality enables scalable “breeding” protocols for non-Gaussian states while greatly reducing hardware overhead. In a proof-of-principle experiment, we realize Schrödinger cat and Gottesman-Kitaev-Preskill state breeding using only a single squeezed single-photon source. We also achieve the first complete demonstration of an optical resonator memory capable of writing, storing, and retrieving quantum states with high efficiency.

Our results establish a practical pathway toward scalable non-Gaussian state generation, advancing prospects for fault-tolerant quantum computing and applications in communication, sensing, and metrology.

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References (45)

  1. W. Asavanant, Y. Shiozawa, S. Yokoyama, B. Charoensombutamon, H. Emura, R. N. Alexander, S. Takeda, J. Yoshikawa, N. C. Menicucci, H. Yonezawa, and A. Furusawa, Generation of time-domain-multiplexed two-dimensional cluster state, Science 366, 373 (2019).
  2. M. V. Larsen, X. Guo, C. R. Breum, J. S. Neergaard-Nielsen, and U. L. Andersen, Deterministic multi-mode gates on a scalable photonic quantum computing platform, Nat. Phys. 17, 1018 (2021).
  3. W. Asavanant, B. Charoensombutamon, S. Yokoyama, T. Ebihara, T. Nakamura, R. N. Alexander, M. Endo, J. Yoshikawa, N. C. Menicucci, H. Yonezawa, and A. Furusawa, Time-domain-multiplexed measurement-based quantum operations with 25-MHz clock frequency, Phys. Rev. Appl. 16, 034005 (2021).
  4. S. D. Bartlett, B. C. Sanders, S. L. Braunstein, and K. Nemoto, Efficient classical simulation of continuous variable quantum information processes, Phys. Rev. Lett. 88, 097904 (2002).
  5. J. Niset, J. Fiurášek, and N. J. Cerf, No-go theorem for Gaussian quantum error correction, Phys. Rev. Lett. 102, 120501 (2009).
  6. D. Gottesman, A. Kitaev, and J. Preskill, Encoding a qubit in an oscillator, Phys. Rev. A 64, 012310 (2001).
  7. A. P. Lund, H. Jeong, T. C. Ralph, and M. S. Kim, Conditional production of superpositions of coherent states with inefficient photon detection, Phys. Rev. A 70, 020101(R) (2004).
  8. H. M. Vasconcelos, L. Sanz, and S. Glancy, All-optical generation of states for “encoding a qubit in an oscillator”, Opt. Lett. 35, 3261 (2010).
  9. M. Eaton, R. Nehra, and O. Pfister, Non-Gaussian and Gottesman–Kitaev–Preskill state preparation by photon catalysis, New J. Phys. 21, 113034 (2019).
  10. D. V. Sychev, A. E. Ulanov, A. A. Pushkina, M. W. Richards, I. A. Fedorov, and A. I. Lvovsky, Enlargement of optical Schrödinger’s cat states, Nat. Photonics 11, 379 (2017).
  11. S. Konno, W. Asavanant, F. Hanamura, H. Nagayoshi, K. Fukui, A. Sakaguchi, R. Ide, F. China, M. Yabuno, S. Miki, H. Terai, K. Takase, M. Endo, P. Marek, R. Filip, P. van Loock, and A. Furusawa, Logical states for fault-tolerant quantum computation with propagating light, Science 383, 289 (2024).
  12. N. T. Arnold, C. P. Lualdi, M. E. Goggin, and P. G. Kwiat, in Quantum Computing, Communication, and Simulation IV, edited by P. R. Hemmer and A. L. Migdall, International Society for Optics and Photonics (SPIE, San Francisco, California, United States, 2024), Vol. 12911, p. 129111C, https://www.spiedigitallibrary.org/conference-proceedings-of-spie/12911/129111C/All-optical-quantum-memory/10.1117/12.3003228.short.
  13. H. Simon, L. Caron, R. Journet, V. Cotte, and R. Tualle-Brouri, Experimental demonstration of a versatile and scalable scheme for iterative generation of non-Gaussian states of light, Phys. Rev. Lett. 133, 173603 (2024).
  14. D. Okuno, T. Yoshida, R. Arita, T. Kashiwazaki, T. Umeki, S. Miki, F. China, M. Yabuno, H. Terai, and S. Takeda, Time-domain programmable beam-splitter operations for an optical phase-sensitive non-Gaussian state, Phys. Rev. A 110, 023706 (2024).
  15. F. Kaneda and P. G. Kwiat, High-efficiency single-photon generation via large-scale active time multiplexing, Sci. Adv. 5, eaaw8586 (2019).
  16. A. Kawasaki, K. Takase, T. Nomura, S. Miki, H. Terai, M. Yabuno, F. China, W. Asavanant, M. Endo, J. Yoshikawa, and A. Furusawa, Generation of highly pure single-photon state at telecommunication wavelength, Opt. Express 30, 24831 (2022).
  17. A. Kawasaki, R. Ide, H. Brunel, T. Suzuki, R. Nehra, K. Nakashima, T. Kashiwazaki, A. Inoue, T. Umeki, F. China, M. Yabuno, S. Miki, H. Terai, T. Yamashima, A. Sakaguchi, K. Takase, M. Endo, W. Asavanant, and A. Furusawa, Broadband generation and tomography of non-Gaussian states for ultra-fast optical quantum processors, Nat. Commun. 15, 9075 (2024).
  18. K. Takase, A. Kawasaki, B. K. Jeong, T. Kashiwazaki, T. Kazama, K. Enbutsu, K. Watanabe, T. Umeki, S. Miki, H. Terai, M. Yabuno, F. China, W. Asavanant, M. Endo, J. Yoshikawa, and A. Furusawa, Quantum arbitrary waveform generator, Sci. Adv. 8, eadd4019 (2022).
  19. A. P. Lund and T. C. Ralph, Coherent-state linear optical quantum computing gates using simplified diagonal superposition resource states, Phys. Rev. A 71, 032305 (2005).
  20. K. Takase, J. Yoshikawa, W. Asavanant, M. Endo, and A. Furusawa, Generation of optical Schrödinger cat states by generalized photon subtraction, Phys. Rev. A 103, 013710 (2021).
  21. H. Tomoda, A. Machinaga, K. Takase, J. Harada, T. Kashiwazaki, T. Umeki, S. Miki, F. China, M. Yabuno, H. Terai, D. Okuno, and S. Takeda, Boosting the generation rate of squeezed single-photon states by generalized photon subtraction, Phys. Rev. A 110, 033717 (2024).
  22. T. Kashiwazaki, T. Yamashima, N. Takanashi, A. Inoue, T. Umeki, and A. Furusawa, Fabrication of low-loss quasi-single-mode PPLN waveguide and its application to a modularized broadband high-level squeezer, Appl. Phys. Lett. 119, 251104 (2021).
  23. S. Miki, M. Yabuno, T. Yamashita, and H. Terai, Stable, high-performance operation of a fiber-coupled superconducting nanowire avalanche photon detector, Opt. Express 25, 6796 (2017).
  24. O. Morin, C. Fabre, and J. Laurat, Experimentally accessing the optimal temporal mode of traveling quantum light states, Phys. Rev. Lett. 111, 213602 (2013).
  25. J. Řeháček, Z. Hradil, E. Knill, and A. I. Lvovsky, Diluted maximum-likelihood algorithm for quantum tomography, Phys. Rev. A 75, 042108 (2007).
  26. Y. Hashimoto, T. Toyama, J. Yoshikawa, K. Makino, F. Okamoto, R. Sakakibara, S. Takeda, P. van Loock, and A. Furusawa, All-optical storage of phase-sensitive quantum states of light, Phys. Rev. Lett. 123, 113603 (2019).
  27. M. V. Larsen et al., Integrated photonic source of Gottesman–Kitaev–Preskill qubits, Nature 642, 587 (2025).
  28. V. G. Matsos, C. H. Valahu, T. Navickas, A. D. Rao, M. J. Millican, X. C. Kolesnikow, M. J. Biercuk, and T. R. Tan, Robust and deterministic preparation of bosonic logical states in a trapped ion, Phys. Rev. Lett. 133, 050602 (2024).
  29. A. Eickbusch, V. Sivak, A. Z. Ding, S. S. Elder, S. R. Jha, J. Venkatraman, B. Royer, S. M. Girvin, R. J. Schoelkopf, and M. H. Devoret, Fast universal control of an oscillator with weak dispersive coupling to a qubit, Nat. Phys. 18, 1464 (2022).
  30. Ç. Ekici, Y. Yu, J. C. Adcock, A. L. Muthali, H. Tan, Z. Lin, H. Li, L. K. Oxenløwe, X. Cai, and Y. Ding, High-resolution single photon level storage of telecom light based on thin film lithium niobate photonics, Adv. Quantum Technol. 8, 2300195 (2025).
  31. J. Wang, F. Sciarrino, A. Laing, and M. G. Thompson, Integrated photonic quantum technologies, Nat. Photonics 14, 273 (2020).
  32. C. Kupchak, J. Erskine, D. England, and B. Sussman, Terahertz-bandwidth switching of heralded single photons, Opt. Lett. 44, 1427 (2019).
  33. M. Endo, R. He, T. Sonoyama, K. Takahashi, T. Kashiwazaki, T. Umeki, S. Takasu, K. Hattori, D. Fukuda, K. Fukui, K. Takase, W. Asavanant, P. Marek, R. Filip, and A. Furusawa, Non-Gaussian quantum state generation by multi-photon subtraction at the telecommunication wavelength, Opt. Express 31, 12865 (2023).
  34. Q. Shi, J. Tian, S. Ding, Y. Wang, S. Lei, M. Zhang, W. Wan, X. Ji, B. He, M. Xiao, and X. Jiang, On-chip ultra-high-Q optical microresonators approaching the material absorption limit, Photonics Res. 13, 2409 (2025).
  35. Y. Arakawa and M. J. Holmes, Progress in quantum-dot single photon sources for quantum information technologies: A broad spectrum overview, Appl. Phys. Rev. 7, 021309 (2020).
  36. F. Hanamura, Dataset for “Scalable optical quantum state synthesizer with dual-mode resonator memory” (2025), https://github.com/fhanamura/dual_mode_memory_data.
  37. U. Chabaud, D. Markham, and F. Grosshans, Stellar representation of non-Gaussian quantum states, Phys. Rev. Lett. 124, 063605 (2020).
  38. D. Su, C. R. Myers, and K. K. Sabapathy, Conversion of Gaussian states to non-Gaussian states using photon-number-resolving detectors, Phys. Rev. A 100, 052301 (2019).
  39. P. Marek, Ground state nature and nonlinear squeezing of Gottesman-Kitaev-Preskill states, Phys. Rev. Lett. 132, 210601 (2024).
  40. K. Takase, K. Fukui, A. Kawasaki, W. Asavanant, M. Endo, J. Yoshikawa, P. van Loock, and A. Furusawa, Gottesman-Kitaev-Preskill qubit synthesizer for propagating light, npj Quantum Inf. 9, 98 (2023).
  41. H. Aghaee Rad et al., Scaling and networking a modular photonic quantum computer, Nature 638, 912 (2025).
  42. K. Takase, F. Hanamura, H. Nagayoshi, J. E. Bourassa, R. N. Alexander, A. Kawasaki, W. Asavanant, M. Endo, and A. Furusawa, Generation of flying logical qubits using generalized photon subtraction with adaptive Gaussian operations, Phys. Rev. A 110, 012436 (2024).
  43. F. Bodog, M. Mechler, M. Koniorczyk, and P. Adam, Optimization of multiplexed single-photon sources operated with photon-number-resolving detectors, Phys. Rev. A 102, 013513 (2020).
  44. C. Joshi, A. Farsi, S. Clemmen, S. Ramelow, and A. L. Gaeta, Frequency multiplexing for quasi-deterministic heralded single-photon sources, Nat. Commun. 9, 847 (2018).
  45. D. J. Weigand and B. M. Terhal, Generating grid states from Schrödinger-cat states without postselection, Phys. Rev. A 97, 022341 (2018).

Outline

Information

PRX Quantum 6, 040336– Published 14 November, 2025
  • Received 17 June 2025
  • Revised 16 August 2025
  • Accepted 7 October 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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