Shot Noise
Introduction
Shot noise, also known as Poisson noise, is a type of electronic noise which can be modeled by a Poisson distribution. It is associated with the discrete nature of electric charge. Shot noise exists because phenomena such as light and electric current consist of the movement of discrete (i.e., quantized) 'packets'.
Discovery and Initial Studies
The concept of shot noise was first introduced by Walter Schottky, a German physicist who was studying fluctuations in current. Schottky's work in the early 20th century was instrumental in developing the theory of shot noise.
Understanding Shot Noise
Shot noise is a fundamental property of systems which are defined by discrete events. In the case of an electrical circuit, these discrete events are the passage of individual electrons. Because these events occur randomly and independently of each other, the current or light produced by the system will exhibit fluctuations in intensity. This fluctuation is what we refer to as shot noise.
Mathematical Description
The mathematical description of shot noise involves the use of probability theory and statistical mechanics. In particular, the Poisson distribution is used to model the randomness of the events causing the noise.
Shot Noise in Electronics
In electronics, shot noise occurs due to the discrete nature of electric charge. It is a significant source of noise in electronic devices and can limit the performance of these devices.
Shot Noise in Optical Systems
Shot noise also occurs in optical systems, where it is caused by the quantization of light into photons. This can limit the performance of optical communication systems, such as fiber-optic communication networks.
Shot Noise in Quantum Mechanics
In quantum mechanics, shot noise can be seen as a manifestation of the Heisenberg uncertainty principle. This is because the discrete events causing the noise can be seen as measurements, which disturb the system and cause uncertainty.
Mitigation of Shot Noise
There are several techniques for mitigating shot noise in electronic and optical systems. These include the use of averaging techniques, error correction methods, and the use of quantum error correction in quantum systems.