Shot Noise

Abstract

The intensity of light is measured by means of photodetectors. The response of a photodetector is a discrete process with random character due to the quantum character of the interaction between light radiation and the material of the photocathode. The term “random character” means that due to the same interaction a photoelectron may or may not be created. We assume that this process can be described only by the probability of photoelectron appearance when atoms of the photocathode are affected by an incident electromagnetic wave. In this chapter we are interested in the statistical properties of the photoeffect but not in statistical properties of the radiation. Thus, we assume monochromatic light radiation, which has no random parameters.