Solid state photon counters and their applications in space related projects

We are presenting a review of the solid state photon counters developed in our laboratories and their applications in various space related projects. The solid state photon counters are the avalanche photodiode structures which are operated in so called Geiger mode, they are pulse biased above their breakdown voltage. In such a stage the first charge carrier generated by a photon or some noise event will trigger an avalanche multiplication of carriers and hence the macroscopic current on the output contacts. The external circuit is used to terminate the avalanche and to set up the bias for the new detection. We have prepared these photon counters on the basis of the common semiconducting materials Silicon, Germanium, SiGe mixture, GaAs, GaP, and GaAsP. The most attractive for applications in space projects is the structure on Si we have prepared using the K14 technology. They have several interesting features in comparison to similar structures prepared in other groups: they do allow detection both single or multiple photon signals and still maintaining picosecond timing resolution and detection delay stability. The detection semiconducting structures are highly tolerant with respect to radiation, what makes the extremely attractive for space applications. For satellite laser ranging we are providing detector package having quantum efficiency reaching 40% at the wavelength of 532 nm, its timing resolution is reaching 20 to 5 picoseconds for the detected signal strength of single to 3000 photons per pulse. The detection delay is stable within 10 ps over an entire dynamical range and the background photon flux reaching 30 Mc/s. The implementation of these detectors into the satellite laser ranging network (along with appropriate laser and timing technologies) resulted in the ranging precision to the space objects on the millimeter level. For the space missions to planets we have prepared photon counting detectors for operation in laser altimeter and atmospheric Lidar. Recently the operation of the Laser Time Transfer experiments on board of the Chinese navigation satellites Compass and on board the French satellite Jason-2 is relying on our photon counters as well. The plans for the future space application will be presented.