Shot Noise in Mesoscopic Conductors

TL;DR

This review discusses the significance of shot noise in mesoscopic conductors, highlighting its role in revealing quasiparticle properties, internal energy scales, and electron interactions beyond conductance measurements.

Contribution

It provides a comprehensive overview of shot noise in mesoscopic physics, including theoretical approaches and unresolved issues, emphasizing its diagnostic power over traditional conductance analysis.

Findings

Shot noise reveals quasiparticle charge and statistics.

Shot noise is more sensitive to electron-electron interactions.

The review identifies open problems and future directions in the field.

Abstract

Theoretical and experimental work concerned with dynamic fluctuations has developed into a very active and fascinating subfield of mesoscopic physics. We present a review of this development focusing on shot noise in small electric conductors. Shot noise is a consequence of the quantization of charge. It can be used to obtain information on a system which is not available through conductance measurements. In particular, shot noise experiments can determine the charge and statistics of the quasiparticles relevant for transport, and reveal information on the potential profile and internal energy scales of mesoscopic systems. Shot noise is generally more sensitive to the effects of electron-electron interactions than the average conductance. We present a discussion based on the conceptually transparent scattering approach and on the classical Langevin and Boltzmann-Langevin methods; in addition a discussion of results which cannot be obtained by these methods is provided. We conclude the review by pointing out a number of unsolved problems and an outlook on the likely future development of the field.