  The Italian institute for nuclear physics (INFN) has financed the SIMP
project (2019-2021) in order to strengthen its skills and technologies in the
field of meV detectors with the ultimate aim of developing a single microwave
photon detector. This goal will be pursued by improving the sensitivity and the
dark count rate of two types of photodetectors: current biased Josephson
Junction (JJ) for the frequency range 10-50 GHz and Transition Edge Sensor
(TES) for the frequency range 30-100 GHz. Preliminary results on materials and
devices characterization are presented.
