An Ultra Compact Tunable Optimised Photonic Ultimate Sampling of Microwave Signals – AUCTOPUSS

The AUCTOPUSS project aims to study and develop a function to digitalize, high dynamics and very wide band, microwave signals by optimizing the sampling operation using semiconductor nanostructured materials.
This research project is motivated by the very promising results obtained during the exploratory research plan, funded within the REI Program framework of the DGA/MRIS, on a "nano photo-switch". These results brought to light that this technological break opened the way to the optical approaches for the sampling of ultra-wide band microwave signals. This break declines as well on the extreme simplicity of the photo-switch device as on its performances which are already far beyond the conventional electronic approaches.
To reach the performances of dynamics required for the civil and military applications, in particular the Spurious Free Dynamic Range (SFDR) and the Signal to Noise Ratio (SNR) or the Effective Number Of Bits (ENOB), a stage of optimization of the switch is absolutely necessary.
The objective of the AUCTOPUSS project is to optimize the performances of the very wide band microwave samplers, by focusing on the photoswitch function. The choice of a nanostructured semiconductor material, optimized in AUCTOPUSS, will allow to have a carriers lifetime compatible with the targeted sampling function (i.e. some ps) and to integrate in the mid-term the pulse light source with very low jitter in the 1550nm window (the optical telecommunications range) by using the two photons absorption process. To optimize such a switch, it was shown in a previous study that it was necessary to improve simultaneously, in the same time, the insertion losses, the carrier lifetime of the semiconductor used for the switching with respect to the optical pulse repetition rate.