QUANTUM IS IN THE EYE OF THE BEHOLDER FOCUS both roles is a challenge that is emerging as a novel direction for quantum technologies [ 11 ]. The system that can be envisioned may consist in a two-beam state exhibiting quantum entanglement, linking the subject Bob to an operator Alice carrying out a measurement remotely. This ensures that Alice, by only sending one half of the total state, gives out limited information to the external world, but her additional knowledge from the second half provides her with means for measuring.
The detailed design of the scheme will demand addressing several trade-off conditions. The first concerns the quantum state itself that will need to be able to measure accurately and precisely as well as to protect the available information by revealing intrusions. A fine balance in its quantum properties should be met for the state to remain robust against imperfections such as loss and, at the same time, testable for security. The second aspect is related to the fact that data transmission typically uses infrared wavelengths, but these have limited applicability to measurements of the retina. This may require sophisticated photonics solutions for the realisation of efficient frequency converters.
CONCLUSION Quantum metrology and cryptography are among the most promising quantum technologies to date, having led already to practical demonstrations and technological applications. Recent investigations into the single-photon detection capabilities of the human eye pave the way for wider usage of quantum-mechanical features in such systems while at the same time calling for considerable steps forward to balance traditional performance measures with medical safety. In taking up this challenge, it will be crucial not to forget
REFERENCES the lesson that the best physical and physiological conditions should be met, and genuine progress would only emerge from collaborative, multidisciplinary efforts.
This new frontier of quantumassisted medical imaging might advance both our fundamental understanding of human vision and our diagnostic capabilities, thanks to the use of lower-intensity signals achieving higher measurement precision and enabling the acquisition of medical data with privacy guaranteed by quantum-mechanical laws.
[ 1 ] S. Kleinlogel, and A. G. White, PLoS ONE 3: e2190( 2008) [ 2 ] A. Russo, A. Boldini, D. Romano et al., J. Ophthalmol. 2022, 1004977( 2022) [ 3 ] E. Polino, M. Valeri, N. Spagnolo, and F. Sciarrino, AVS Quantum Sci. 2, 024703( 2020) [ 4 ] S. Hecht, S. Shlaer, and M. H. Pirenne, J. Gen. Physiol. 25, 819( 1942) [ 5 ] F. Rieke and D. A. Baylor, Rev. Mod. Phys. 70, 1027( 1998) [ 6 ] N. M. Phan, M. F. Cheng, D. A. Bessarab, and L. A. Krivitsky Phys. Rev. Lett. 112, 213601( 2014) [ 7 ] J. N. Tinsely, M. I. Molodtsov, R. Prevedel, et al., Nat. Commun. 7, 12172( 2016) [ 8 ] Q. Li, K. Orcutt, R. L. Cook, et al., Nature 619, 300-304( 2023) [ 9 ] T. H. A. van der Reep, D. Molenaar, W. Löffler, and Y. Pinto, J. Opt. Soc. Am. A 40, 285( 2023) [ 10 ] M. Loulakis, G. Blatsios, C. S. Vrettou, and I. K. Kominis, Phys. Rev. Res. 8, 044012( 2017) [ 11 ] Z. Huang, C. Macchiavello, and L. Maccone, Phys. Rev. A 99, 022314( 2019)
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