Shot Noise in Mesoscopic Systems: From Single Particles to Quantum Liquids

Shot noise, originating from the discrete nature of electric charge, is generated by scattering processes. Shot-noise measurements have revealed microscopic charge dynamics in various quantum transport phenomena. In particular, beyond the single-particle picture, such measurements have proved to be powerful ways to investigate electron correlation in quantum liquids. Here, we review the recent progress of shot-noise measurements in mesoscopic physics. This review summarizes the basics of shot-noise theory based on the Landauer–Büttiker formalism, measurement techniques used in previous studies, and several recent experiments demonstrating electron scattering processes. We then discuss three different kinds of quantum liquids, namely those formed by, respectively, the Kondo effect, the fractional quantum Hall effect, and superconductivity. Finally, we discuss current noise within the framework of nonequilibrium statistical physics and review related experiments. We hope that this review will convey the significance of shot-noise measurements to a broad range of researchers in condensed matter physics.