Data / Hora
Date(s) - 27/11/2025
17:00 - 18:45
Categorias
COLÓQUIO DO DEPARTAMENTO DE FÍSICA
Disordered photonic systems for physical cryptography
F. Riboli
Istituto Nazionale di Ottica (INO), CNR, 50019 Sesto Fiorentino, Italy
European Laboratory for Non-linear Spectroscopy (LENS), Sesto Fiorentino (FI), Italy
5a. feira – 27 de novembro – às 17:00 – sala L774
In this talk, I will give a brief introduction to my research activity in the field of disordered photonics, which includes fundamental concepts in multiple scattering of light [1] and their possible applications for photonic optical limiters and asymmetric transmission of light [2].
The talk will then focus on physical cryptography, specifically secret-free security using so-called Physical Unclonable Functions (PUFs), also known as Physical One-Way Functions. These systems are believed to be, up to today, physically and mathematically unclonable—easy to evaluate yet difficult to invert. PUFs are considered the modern realization of the ancient concept of a key, as they allow the allocation and authentication of unique identifiers by converting a medium’s microstructure into a string of binary digits. Indeed, PUFs can be used for authentication and anti-counterfeiting.
I will present our results on linear and reconfigurable optical PUFs [3], quantifying the entropies of the generated keys, the degree of unclonability [4] and discussing strategies to further increase the security of this class of cryptographic primitives, specifically by adding nonlinearities and quantum read-out authentication schemes.
References
[1] F. Riboli, et al, “Engineering of light confinement in strongly scattering disordered media”, Nature Materials 13, 720-725 (2014).
[2] F. Riboli, et al, “Optical limiter based on PT-symmetry breaking of reflectionless modes”, Optica 10, 1302-1309 (2023).
[3] Nocentini, S., Rührmair, U., Barni, M. Wiersma, D.S., and Riboli, F., All-optical multilevel physical unclonable functions. Nature Materials 23, 369–376 (2024).
[4] G. E. Lio, S. Nocentini, L. Pattelli, E. Cara, D. S. Wiersma, U. Rührmair, F. Riboli, “Quantifying the sensitivity and unclonability of optical physical unclonable functions”, Advanced Photonics Research, 4, 2200225 (2023).
