  The PICOSEC detection concept consists in a "two-stage" Micromegas detector
coupled to a Cherenkov radiator and equipped with a photocathode. A proof of
concept has already been tested: a single-photoelectron response of 76 ps has
been measured with a femtosecond UV laser at CEA/IRAMIS, while a time
resolution of 24 ps with a mean yield of 10.4 photoelectrons has been measured
for 150 GeV muons at the CERN SPS H4 secondary line. This work will present the
main results of this prototype and the performance of the different detector
configurations tested in 2016-18 beam campaigns: readouts (bulk, resistive,
multipad) and photocathodes (metallic+CsI, pure metallic, diamond). Finally,
the prospects for building a demonstrator based on PICOSEC detection concept
for future experiments will be discussed. In particular, the scaling strategies
for a large area coverage with a multichannel readout plane, the R\&D on solid
converters for building a robust photocathode and the different resistive
configurations for a robust readout.
