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Published March 8, 2024 | Published
Journal Article Open

Quantum imaging of biological organisms through spatial and polarization entanglement

  • 1. ROR icon California Institute of Technology


Quantum imaging holds potential benefits over classical imaging but has faced challenges such as poor signal-to-noise ratios, low resolvable pixel counts, difficulty in imaging biological organisms, and inability to quantify full birefringence properties. Here, we introduce quantum imaging by coincidence from entanglement (ICE), using spatially and polarization-entangled photon pairs to overcome these challenges. With spatial entanglement, ICE offers higher signal-to-noise ratios, greater resolvable pixel counts, and the ability to image biological organisms. With polarization entanglement, ICE provides quantitative quantum birefringence imaging capability, where both the phase retardation and the principal refractive index axis angle of an object can be remotely and instantly quantified without changing the polarization states of the photons incident on the object. Furthermore, ICE enables 25 times greater suppression of stray light than classical imaging. ICE has the potential to pave the way for quantum imaging in diverse fields, such as life sciences and remote sensing.

Copyright and License

© 2024 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution License 4.0 (CC BY).


We thank P. Prober and T. Cammidge for preparing the zebrafish specimen. We thank L. Li for preparing the brain slice. We thank P. Wang and L. Lin for assistance with the experiment. We also thank K. Titimbo Chaparro and S. Suleyman Kahraman for discussion.


This project has been made possible in part by Caltech’s Center for Sensing to Intelligence, grant number 2020-225832 from the Chan Zuckerberg Initiative DAF, an advised fund of Silicon Valley Community Foundation, and National Institutes of Health grants R35 CA220436 (Outstanding Investigator Award) and R01 EB028277.


Y.Z., Z.H., and X.T. built the imaging system, performed the experiments, and analyzed the data. Y.Z. developed the data acquisition program. Z.H. developed the quantum imaging theory. X.T. developed the sub-shot-noise algorithms. Y.Z. and X.T. developed the quantitative quantum birefringence imaging theory and algorithms. Y.Z., Z.H., X.T., and D.C.G. prepared the manuscript. R.C. prepared the agarose-embedded zebrafish and carbon fibers. L.V.W. conceived the concept and supervised the project. All authors contributed to writing the manuscript.

Data Availability

All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials.

Conflict of Interest

The authors declare that they have no competing interests.


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Additional details

March 11, 2024
March 21, 2024