Recent developments in pixellated avalanche photodiodes

A new generation of solid state devices can provide functionality in many cases comparable to, and in some cases better than photomultipliers. By constructing a finely pixellated avalanche photodiode such that each pixel can operate independently in Geiger mode without triggering its neighbours one can combine the simple biasing and high gain of traditional avalanche mode operation with proportionality provided the number of incident photons is significantly less than the number of pixels. We have been studying devices of this kind from Photonique and report on their performance both stand-alone and in conjunction with scintillators and make projections as to their suitability for a wide range of applications. The high quantum efficiencies and very fast response times of these devices open up whole new opportunities. Faithful to the conference record, this paper predominantly shows graphical data