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  • Open Access

Temporally Localized Quantum Operations on Continuous-Wave Thermal Light

Yunkai Wang*,†, Yujie Zhang‡, and Virginia O. Lorenz

  • *Contact author: ywang10@perimeterinstitute.ca
  • †Present address: Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2L 2Y5, Canada and Institute for Quantum Computing and Department of Applied Mathematics, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
  • ‡Present address: Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2L 2Y5, Canada and Institute for Quantum Computing and Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
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Phys. Rev. Lett. 135, 113602 – Published 10 September, 2025

DOI: https://doi.org/10.1103/y4v8-1wgm

Abstract

Previous work showed that thermal light with a blackbody spectrum cannot be decomposed into a mixture of independent localized pulses. However, we find that in the weak-source limit and under the assumption of a flat spectrum, the first nonvacuum term in the state expansion does form a mixture of such pulses. This decomposition is essential for quantum-enhanced astronomical interferometry, which typically operates on localized pulses even though stellar light is inherently continuous-wave. We present a quantum derivation of the van Cittert–Zernike theorem that incorporates finite bandwidth, thereby justifying the operations on localized pulses while processing continuous-wave thermal light. For general spectra in the weak-source limit, we establish a criterion under which correlations between pulses can be safely neglected. When this criterion is not met, we provide a corrected strategy that accurately accounts for both the spectral profile and the detector-defined pulse shape.

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References (28)

  1. L. Mandel and E. Wolf, Optical Coherence and Quantum Optics (Cambridge University Press, Cambridge, England, 1995).
  2. D. Gottesman, T. Jennewein, and S. Croke, Longer-baseline telescopes using quantum repeaters, Phys. Rev. Lett. 109, 070503 (2012).
  3. L.-M. Duan and C. Monroe, Colloquium: Quantum networks with trapped ions, Rev. Mod. Phys. 82, 1209 (2010).
  4. S.-H. Wei, B. Jing, X.-Y. Zhang, J.-Y. Liao, C.-Z. Yuan, B.-Y. Fan, C. Lyu, D.-L. Zhou, Y. Wang, G.-W. Deng et al., Towards real-world quantum networks: A review, Laser Photonics Rev. 16, 2100219 (2022).
  5. N. Sangouard, C. Simon, H. De Riedmatten, and N. Gisinj, Quantum repeaters based on atomic ensembles and linear optics, Rev. Mod. Phys. 83, 33 (2011).
  6. K. Azuma, S. E. Economou, D. Elkouss, P. Hilaire, L. Jiang, H.-K. Lo, and I. Tzitrin, Quantum repeaters: From quantum networks to the quantum internet, Rev. Mod. Phys. 95, 045006 (2023).
  7. E. T. Khabiboulline, J. Borregaard, K. De Greve, and M. D. Lukin, Quantum-assisted telescope arrays, Phys. Rev. A 100, 022316 (2019).
  8. E. T. Khabiboulline, J. Borregaard, K. De Greve, and M. D. Lukin, Optical interferometry with quantum networks, Phys. Rev. Lett. 123, 070504 (2019).
  9. R. Czupryniak, J. Steinmetz, P. G. Kwiat, and A. N. Jordan, Optimal qubit circuits for quantum-enhanced telescopes, Phys. Rev. A 108, 052408 (2023).
  10. R. Czupryniak, E. Chitambar, J. Steinmetz, and A. N. Jordan, Quantum telescopy clock games, Phys. Rev. A 106, 032424 (2022).
  11. M. M. Marchese and P. Kok, Large baseline optical imaging assisted by single photons and linear quantum optics, Phys. Rev. Lett. 130, 160801 (2023).
  12. Z. Huang, B. Q. Baragiola, N. C. Menicucci, and M. M. Wilde, Limited quantum advantage for stellar interferometry via continuous-variable teleportation, Phys. Rev. A 109, 052434 (2024).
  13. Y. Wang, Y. Zhang, and V. O. Lorenz, Astronomical interferometry using continuous variable quantum teleportation, Phys. Rev. Res. 7, 023154 (2025).
  14. B. Purvis, R. Lafler, and R. N. Lanning, Practical approach to extending baselines of telescopes using continuous-variable quantum information, New J. Phys. 26, 103006 (2024).
  15. Y. Zhang and T. Jennewein, Criteria for optimal entanglement-assisted long baseline imaging protocols, arXiv:2501.16670.
  16. A. Chenu, A. M. Brańczyk, and J. E. Sipe, First-order decomposition of thermal light in terms of a statistical mixture of single pulses, Phys. Rev. A 91, 063813 (2015).
  17. A. Chenu, A. M. Brańczyk, G. D. Scholes, and J. E. Sipe, Thermal light cannot be represented as a statistical mixture of single pulses, Phys. Rev. Lett. 114, 213601 (2015).
  18. A. M. Brańczyk, A. Chenu, and J. Sipe, Thermal light as a mixture of sets of pulses: The quasi-1d example, J. Opt. Soc. Am. B 34, 1536 (2017).
  19. R. J. Glauber, The quantum theory of optical coherence, Phys. Rev. 130, 2529 (1963).
  20. R. H. Brown and R. Q. Twiss, Correlation between photons in two coherent beams of light, Nature (London) 177, 27 (1956).
  21. R. Hanbury Brown and R. Q. Twiss, A test of a new type of stellar interferometer on sirius, in A Source Book in Astronomy and Astrophysics, 1900–1975 (Harvard University Press, Cambridge, MA, 1979), pp. 8–12.
  22. J. D. Monnier, Optical interferometry in astronomy, Rep. Prog. Phys. 66, 789 (2003).
  23. K. J. Blow, R. Loudon, S. J. D. Phoenix, and T. J. Shepherd, Continuum fields in quantum optics, Phys. Rev. A 42, 4102 (1990).
  24. P. P. Rohde, W. Mauerer, and C. Silberhorn, Spectral structure and decompositions of optical states, and their applications, New J. Phys. 9, 91 (2007).
  25. See Supplemental Material at http://link.aps.org/supplemental/10.1103/y4v8-1wgm, which includes Refs. [26,27], for more information about the detailed proofs and additional discussions.
  26. C. Weedbrook, S. Pirandola, R. García-Patrón, N. J. Cerf, T. C. Ralph, J. H. Shapiro, and S. Lloyd, Gaussian quantum information, Rev. Mod. Phys. 84, 621 (2012).
  27. U. Leonhardt, Quantum physics of simple optical instruments, Rep. Prog. Phys. 66, 1207 (2003).
  28. , Thermal-light, GitHub repository, Code used for the numerical calculations in the Supplemental Material, 2025, https://github.com/ykwang-phys/thermal-light.

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Phys. Rev. Lett. 135, 113602– Published 10 September, 2025
  • Received 24 December 2024
  • Accepted 18 August 2025
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