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  • Open Access

High-Performance Spin-State Memory for Telecom Quantum Information Applications

James Stuart*, Kieran Smith, Morgan Hedges, Rose Ahlefeldt, and Matthew Sellars

  • *Contact author: james.stuart@anu.edu.au
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PRX Quantum 7, 043031 – Published 13 November, 2026

DOI: https://doi.org/10.1103/bgbx-ph24

Abstract

Optical quantum memories based on Er, with its telecom-compatible optical transition, could benefit quantum networking and linear optics quantum computing applications, if the requirements for high memory efficiency, fidelity, and storage capacity can be met simultaneously. Here, we demonstrate the first high efficiency memory in Er, with spin-state storage for 25  μs and classical efficiencies up to 81%, using the rephased amplified spontaneous emission protocol. We show quantum storage along with high-fidelity entanglement of an output state and the state stored in memory, and a demonstration of multiplexing, storing 70 modes in the temporal domain. We use the results to discuss how, with modifications to the pulse sequences and experimental geometry only, the performance can be improved to meet the requirements for practical quantum applications.

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Quantum memories are important components in future optical quantum networks and light-based quantum computers, where they allow synchronization and sequencing information. A truly useful quantum memory must, simultaneously, be compatible with existing telecommunications operating frequencies; store information with high efficiency and high fidelity; have a large storage capacity; and for networking, have a long storage time. Meeting all these requirements has been a major challenge. In this work, we introduce a quantum memory that naturally operates in the telecom C-band, the same range used in global fiber networks and current light-based quantum computers, and achieves strong performance across all key metrics. Our approach uses an erbium-based crystal and a photon-echo protocol to store light efficiently and in large quantities. We demonstrate record-high efficiency for a solid-state memory and show that the system can achieve high capacity storage while maintaining compatibility with long storage times. These results closely match theoretical predictions and push the limits of the simple experimental design used. Looking forward, our simulations show that simple improvements to our optical control and experimental setup are sufficient to push efficiency above 90%, extend storage times to seconds, and enable storage across thousands of channels. Such capabilities would make erbium-based memories practical for real-world quantum networks and even outperform fiber delay lines in quantum computers, marking a major step toward scalable optical quantum technologies.

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References (66)

  1. N. Sangouard, C. Simon, H. de Riedmatten, and N. Gisin, Quantum repeaters based on atomic ensembles and linear optics, Rev. Mod. Phys. 83, 33 (2011).
  2. W. Tittel, M. Afzelius, T. Chaneliére, R. L. Cone, S. Kröll, S. A. Moiseev, and M. Sellars, Photon-echo quantum memory in solid state systems, Laser Photonics Rev. 4, 244 (2010).
  3. H. Choi, M. Pant, S. Guha, and D. Englund, Percolation-based architecture for cluster state creation using photon-mediated entanglement between atomic memories, npj Quantum Inf. 5, 1 (2019).
  4. A. D. Manukhova, K. S. Tikhonov, T. Y. Golubeva, and Y. M. Golubev, Noiseless signal shaping and cluster-state generation with a quantum memory cell, Phys. Rev. A 96, 023851 (2017).
  5. R. Raussendorf and H. J. Briegel, A one-way quantum computer, Phys. Rev. Lett. 86, 5188 (2001).
  6. M. A. Nielsen, Optical quantum computation using cluster states, Phys. Rev. Lett. 93, 040503 (2004).
  7. P. S. Mundada, A. Khindanov, Y. Wang, C. L. Edmunds, P. Coote, M. J. Biercuk, Y. Baum, and M. Hush, Heterogeneous architectures enable a 138× reduction in physical qubit requirements for fault-tolerant quantum computing under detailed accounting, arXiv:2604.06319.
  8. S. A. Moiseev and S. N. Andrianov, A quantum computer on the basis of an atomic quantum transistor with built-in quantum memory, Opt. Spectrosc. 121, 886 (2016).
  9. M. Hosseini, S. Rebić, B. M. Sparkes, J. Twamley, B. C. Buchler, and P. K. Lam, Memory-enhanced noiseless cross-phase modulation, Light Sci. Appl. 1, e40 (2012).
  10. A. C. Leung, K. S. I. Melody, A. D. Tranter, K. V. Paul, G. T. Campbell, P. K. Lam, and B. C. Buchler, Observation of cross phase modulation in cold atom gradient echo memory, New J. Phys. 24, 093011 (2022).
  11. S. Yokoyama, R. Ukai, S. C. Armstrong, C. Sornphiphatphong, T. Kaji, S. Suzuki, J.-I. Yoshikawa, H. Yonezawa, N. C. Menicucci, and A. Furusawa, Ultra-large-scale continuous-variable cluster states multiplexed in the time domain, Nat. Photonics 7, 982 (2013).
  12. S. Muralidharan, L. Li, J. Kim, N. Lütkenhaus, M. D. Lukin, and L. Jiang, Optimal architectures for long distance quantum communication, Sci. Rep. 6, 20463 (2016).
  13. L.-M. Duan, M. D. Lukin, J. I. Cirac, and P. Zoller, Long-distance quantum communication with atomic ensembles and linear optics, Nature (London) 414, 413 (2001).
  14. P. M. Ledingham, W. R. Naylor, J. J. Longdell, S. E. Beavan, and M. J. Sellars, Nonclassical photon streams using rephased amplified spontaneous emission, Phys. Rev. A 81, 012301 (2010).
  15. M. Razavi, M. Piani, and N. Lütkenhaus, Quantum repeaters with imperfect memories: Cost and scalability, Phys. Rev. A 80, 032301 (2009).
  16. M. P. Hedges, J. J. Longdell, Y. Li, and M. J. Sellars, Efficient quantum memory for light, Nature (London) 465, 1052 (2010).
  17. D. Schraft, M. Hain, N. Lorenz, and T. Halfmann, Stopped light at high storage efficiency in a Pr3+:Y2SiO5 crystal, Phys. Rev. Lett. 116, 073602 (2016).
  18. M. Hosseini, B. M. Sparkes, G. Campbell, P. K. Lam, and B. C. Buchler, High efficiency coherent optical memory with warm rubidium vapour, Nat. Commun. 2, 174 (2011).
  19. Y.-F. Hsiao, P.-J. Tsai, H.-S. Chen, S.-X. Lin, C.-C. Hung, C.-H. Lee, Y.-H. Chen, Y.-F. Chen, I. A. Yu, and Y.-C. Chen, Highly efficient coherent optical memory based on electromagnetically induced transparency, Phys. Rev. Lett. 120, 183602 (2018).
  20. M. Cao, Félix Hoffet, S. Qiu, A. S. Sheremet, and J. Laurat, Efficient reversible entanglement transfer between light and quantum memories, Optica 7, 1440 (2020).
  21. Y. Wang, J. Li, S. Zhang, K. Su, Y. Zhou, K. Liao, S. Du, H. Yan, and S.-L. Zhu, Efficient quantum memory for single-photon polarization qubits, Nat. Photonics 13, 346 (2019).
  22. J. Guo, Z. Wu, G. Bao, P. Yang, Y. Wu, L. Q. Chen, and W. Zhang, Near-perfect broadband quantum memory enabled by intelligent spinwave compaction, Phys. Rev. Lett. 135, 170802 (2025).
  23. K. Alexander, A. Benyamini, D. Black, D. Bonneau, S. Burgos, B. Burridge, H. Cable, G. Campbell, G. Catalano, A. Ceballos, C.-M. Chang, S. S. Choudhury, C. J. Chung, F. Danesh, and T. Dauer PsiQuantum team, A manufacturable platform for photonic quantum computing, Nature (London) 641, 876 (2025).
  24. T. Böttger, C. W. Thiel, R. L. Cone, and Y. Sun, Effects of magnetic field orientation on optical decoherence in Er3+:Y2SiO5, Phys. Rev. B 79, 115104 (2009).
  25. Mš Rančić, M. P. Hedges, R. L. Ahlefeldt, and M. J. Sellars, Coherence time of over a second in a telecom-compatible quantum memory storage material, Nat. Phys. 14, 50 (2018).
  26. J. S. Stuart, M. Hedges, R. Ahlefeldt, and M. Sellars, Initialization protocol for efficient quantum memories using resolved hyperfine structure, Phys. Rev. Res. 3, L032054 (2021).
  27. V. Damon, M. Bonarota, A. Louchet-Chauvet, T. Chanelière, and J.-L. Le Gouët, Revival of silenced echo and quantum memory for light, New J. Phys. 13, 093031 (2011).
  28. M. M. Minnegaliev, K. I. Gerasimov, T. N. Sabirov, R. V. Urmancheev, and S. A. Moiseev, Implementation of an optical quantum memory protocol in the Er3+:Y2SiO5 crystal, JETP Lett. 115, 720 (2022).
  29. M. M. Minnegaliev, K. I. Gerasimov, and S. A. Moiseev, Implementation of a quantum memory protocol based on the revival of silenced echo in orthogonal geometry at the telecommunication wavelength, JETP Lett. 117, 865 (2023).
  30. S. E. Beavan, M. P. Hedges, and M. J. Sellars, Demonstration of photon-echo rephasing of spontaneous emission, Phys. Rev. Lett. 109, 093603 (2012).
  31. K. R. Ferguson, S. E. Beavan, J. J. Longdell, and M. J. Sellars, Generation of light with multimode time-delayed entanglement using storage in a solid-state spin-wave quantum memory, Phys. Rev. Lett. 117, 020501 (2016).
  32. C. Li, C. Wyon, and R. Moncorge, Spectroscopic properties and fluorescence dynamics of Er3+ and Yb3+ in Y2SiO5, IEEE J. Quantum Electron. 28, 1209 (1992).
  33. Y. Sun, T. Böttger, C. W. Thiel, and R. L. Cone, Magnetic g tensors for the I15/24 and I13/24 states of Er3+:Y2SiO5, Phys. Rev. B 77, 085124 (2008).
  34. M. Rancic. Ph.D. thesis, Laser Physics Centre, Research School of Physics and Engineering, The Australian National University, 2017.
  35. E. Saglamyurek, J. Jin, V. B. Verma, M. D. Shaw, F. Marsili, S. W. Nam, D. Oblak, and W. Tittel, Quantum storage of entangled telecom-wavelength photons in an erbium-doped optical fibre, Nat. Photonics 9, 83 (2015).
  36. B. Lauritzen, J. Minář, H. de Riedmatten, M. Afzelius, N. Sangouard, C. Simon, and N. Gisin, Telecommunication-wavelength solid-state memory at the single photon level, Phys. Rev. Lett. 104, 080502 (2010).
  37. C. K. Duda, K. R. Ferguson, R. L. Ahlefeldt, M. P. Hedges, and M. J. Sellars, Optimizing the efficiency of a quantum memory based on rephased amplified spontaneous emission, Phys. Rev. A 107, L030602 (2023).
  38. P. M. Ledingham, W. R. Naylor, and J. J. Longdell, Experimental realization of light with time-separated correlations by rephasing amplified spontaneous emission, Phys. Rev. Lett. 109, 093602 (2012).
  39. Y.-Z. Ma, M. Jin, D.-L. Chen, Z.-Q. Zhou, C.-F. Li, and G.-C. Guo, Elimination of noise in optically rephased photon echoes, Nat. Commun. 12, 4378 (2021).
  40. L. A. Williamson and J. J. Longdell, Cavity enhanced rephased amplified spontaneous emission, New J. Phys. 16, 073046 (2014).
  41. B. S. Ham and P. R. Hemmer, Population shelved all-optical modulation, Phys. Rev. B 68, 073102 (2003).
  42. M. Afzelius, I. Usmani, A. Amari, B. Lauritzen, A. Walther, C. Simon, N. Sangouard, J. Minář, H. de Riedmatten, N. Gisin, and S. Kröll, Demonstration of atomic frequency comb memory for light with spin-wave storage, Phys. Rev. Lett. 104, 040503 (2010).
  43. M. Gündoğan, P. M. Ledingham, K. Kutluer, M. Mazzera, and H. de Riedmatten, Solid state spin-wave quantum memory for time-bin qubits, Phys. Rev. Lett. 114, 230501 (2015).
  44. N. Timoney, B. Lauritzen, I. Usmani, M. Afzelius, and N. Gisin, Atomic frequency comb memory with spin-wave storage in Eu3+153:Y2SiO5, J. Phys. B 45, 124001 (2012).
  45. K. R. Ferguson. Ph.D. thesis, Laser Physics Centre, Research School of Physics and Engineering, College of Physical and Mathematical Sciences, 2016.
  46. P. Jobez, I. Usmani, N. Timoney, C. Laplane, N. Gisin, and M. Afzelius, Cavity-enhanced storage in an optical spin-wave memory, New J. Phys. 16, 083005 (2014).
  47. M. Sabooni, Q. Li, S. Kröll, and L. Rippe, Efficient quantum memory using a weakly absorbing sample, Phys. Rev. Lett. 110, 133604 (2013).
  48. S. Duranti, Sören Wengerowsky, L. Feldmann, A. Seri, B. Casabone, and H. de Riedmatten, Efficient cavity-assisted storage of photonic qubits in a solid-state quantum memory, Opt. Express 32, 26884 (2024).
  49. R.-R. Meng, P.-X. Liu, X. Liu, T.-X. Zhu, P.-J. Liang, C. Zhang, Z.-Y. Tang, H.-Z. Zhang, J.-M. Cui, M. Jin, Z.-Q. Zhou, C.-F. Li, and G.-C. Guo, Efficient integrated quantum memory for light, Nat. Photonics 20, 437 (2026).
  50. M. H. Levitt, Composite pulses, Prog. Nucl. Magn. Reson. Spectrosc. 18, 61 (1986).
  51. J. Minář, N. Sangouard, M. Afzelius, H. de Riedmatten, and N. Gisin, Spin-wave storage using chirped control fields in atomic frequency comb-based quantum memory, Phys. Rev. A 82, 042309 (2010).
  52. F. de Seze, F. Dahes, V. Crozatier, I. Lorgeré, F. Bretenaker, and J.-L. Le Gouët, Coherent driving of Tm3+:YAG ions using a complex hyperbolic secant optical field, Eur. Phys. J. D 33, 343 (2005).
  53. R. L. Ahlefeldt, A. Lyasota, J. Smith, J. Ren, and M. J. Sellars, Effect of a hybrid transition moment on Stark-modulated photon echoes in Er3+:Y2SiO5, Phys. Rev. B 108, 195122 (2023).
  54. L.-M. Duan, G. Giedke, J. I. Cirac, and P. Zoller, Inseparability criterion for continuous variable systems, Phys. Rev. Lett. 84, 2722 (2000).
  55. M. Zhong, M. P. Hedges, R. L. Ahlefeldt, J. G. Bartholomew, S. E. Beavan, S. M. Wittig, J. J. Longdell, and M. J. Sellars, Optically addressable nuclear spins in a solid with a six-hour coherence time, Nature (London) 517, 177 (2015).
  56. S. E. Beavan, P. M. Ledingham, J. J. Longdell, and M. J. Sellars, Photon echo without a free induction decay in a double-Λ system, Opt. Lett. 36, 1272 (2011).
  57. M. Afzelius, C. Simon, H. de Riedmatten, and N. Gisin, Multimode quantum memory based on atomic frequency combs, Phys. Rev. A 79, 052329 (2009).
  58. G. Hétet, J. J. Longdell, A. L. Alexander, P. K. Lam, and M. J. Sellars, Electro-optic quantum memory for light using two-level atoms, Phys. Rev. Lett. 100, 023601 (2008).
  59. Y. Ma, Y.-Z. Ma, Z.-Q. Zhou, C.-F. Li, and G.-C. Guo, One-hour coherent optical storage in an atomic frequency comb memory, Nat. Commun. 12, 2381 (2021).
  60. G. Heinze, C. Hubrich, and T. Halfmann, Stopped light and image storage by electromagnetically induced transparency up to the regime of one minute, Phys. Rev. Lett. 111, 033601 (2013).
  61. M. Businger, L. Nicolas, T. S. Mejia, A. Ferrier, P. Goldner, and M. Afzelius, Non-classical correlations over 1250 modes between telecom photons and 979-nm photons stored in Yb3+171:Y2SiO5, Nat. Commun. 13, 6438 (2022).
  62. J. V. Rakonjac, S. Grandi, S. Wengerowsky, D. Lago-Rivera, F. Appas, and H. d. Riedmatten, Transmission of light–matter entanglement over a metropolitan network, Opt. Quantum 1, 94 (2023).
  63. C. M. Knaut, A. Suleymanzade, Y.-C. Wei, D. R. Assumpcao, P.-J. Stas, Y. Q. Huan, B. Machielse, E. N. Knall, M. Sutula, G. Baranes, N. Sinclair, C. De-Eknamkul, D. S. Levonian, M. K. Bhaskar, H. Park, M. Lončar, and M. D. Lukin, Entanglement of nanophotonic quantum memory nodes in a telecom network, Nature (London) 629, 573 (2024).
  64. J.-L. Liu, X.-Y. Luo, Y. Yu, C.-Y. Wang, B. Wang, Y. Hu, J. Li, M.-Y. Zheng, B. Yao, Z. Yan, D. Teng, J.-W. Jiang, X.-B. Liu, X.-P. Xie, J. Zhang, Q.-H. Mao, X. Jiang, Q. Zhang, X.-H. Bao, and J.-W. Pan, Creation of memory–memory entanglement in a metropolitan quantum network, Nature (London) 629, 579 (2024).
  65. Y. Zhou, P. Malik, F. Fertig, M. Bock, T. Bauer, T. van Leent, W. Zhang, C. Becher, and H. Weinfurter, Long-lived quantum memory enabling atom-photon entanglement over 101 km of telecom fiber, PRX Quantum 5, 020307 (2024).
  66. Y. Zhou, P. Malik, F. Fertig, M. Bock, T. Bauer, T. van Leent, W. Zhang, C. Becher, and H. Weinfurter, SQUIRE group quantum memory data. Erbium RASE data set, 2022–2023, relating to paper High efficiency quantum memory for linear optics quantum information applications (2025), 10.25911/fcw8-3676

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PRX Quantum 7, 043031– Published 13 November, 2026
  • Received 9 December 2025
  • Revised 29 June 2026
  • Accepted 23 September 2026
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