A comment on quantum detection

Artur Czerwiński, Jakub J. Borkowski

The paper [Opt. Express32, 40150 (2024)10.1364/OE.531674] investigates quantum illumination using polarization-entangled photon pairs for object detection in noisy environments. In this comment, we identify errors in the mathematical model for photon loss, particularly in the treatment of quantum entanglement under lossy channels. We show that the claimed robustness of polarization entanglement to photon loss contradicts established principles in quantum information theory, rendering the conclusions on detecting low-reflectivity objects unsupported.

Sara Botelho-Andrade, Peter G. Casazza, Desai Cheng +2 more

Ivo Pietro Degiovanni, Ivano Ruo Berchera, Stefania Castelletto +4 more

In this Reply we propose a modified security proof of the quantum dense key distribution protocol, detecting also the eavesdropping attack proposed by W\'ojcik in his Comment [W\'ojcik, Phys. Rev. A 71, 016301 (2005)].

François Chapeau‐Blondeau

Thomas Durt

We study in this short comment the analogies and the differences that exist between several local hidden variable models.

Masao Osaki