O-band QKD link over a multiple ONT loaded carrier-grade GPON for FTTH applications.

We have successfully demonstrated the integration of a commercial O-band Quantum Key Distribution (QKD) system over a testbed that replicates a carrier-grade Fiber-to-the-Home (FTTH) optical access network consisting of components and systems installed in real-life FTTH operational deployments. The experiment demonstrated a QKD transmission over a 1:16 user Gigabit Optical Passive Network (GPON) configuration featuring a total of 9 Optical Network Terminals (ONTs) at the premises of the Telecom Operator COSMOTE that followed the operator's standard FTTH divided in two splitting stages. The architecture we implemented was a downstream access network with the quantum transmitter located at the operator's Central Office (CO) and the quantum receiver located on the end user's side.

Transmission measurements in wedge-shaped absorbing samples: an experiment for observing negative refraction.

We report on experiments of light transmissivity, at wavelengths of 532 nm and 400 nm, through an Au film with a wedge shape. Our results exhibit a resemblance with those reported for observing negative refraction in proposed left-handed materials. This resemblance is present even though the medium that we used is well known to be right handed with its refractive index, therefore, having a positive real part.