Reproducibility of artificial multiple scattering media

Secure authentication is a necessity and an active research field. A promising trend in authentication systems depends on physical unclonable functions (PUF) as keys. Their unclonability is assumed to be assured by technological constraints.
Recently, a quantum-secure authentication (QSA) system was introduced which exploits a multiple scattering medium as a PUF. A scattering medium will create a unique response under coherent illumination called a speckle pattern. Speckle patterns are very sensitive to the location and shape of the numerous scatterers in the medium. Therefore, a scattering medium is considered to be an ideal PUF. We attempt to falsify this assumption by investigating the possibility to create replicas of a multiple scattering medium using direct laser writing.