What is novel in quantum transport for mesoscopics?

TL;DR

This paper discusses the fundamental aspects of quantum transport in mesoscopic systems, emphasizing the role of dissipation and many-body quantum theory in understanding conductance and resistance.

Contribution

It highlights the importance of dissipation and conservation principles in quantum transport, challenging the view that mesoscopic conductance is solely due to coherent single-electron transmission.

Findings

Discretization of conductance is not the only key feature of mesoscopic transport.

Dissipation plays a crucial role even in ballistic quantum point contacts.

Many-body quantum theory explains energy dissipation in quantum conductance.

Abstract

The understanding of mesoscopic transport has now attained an ultimate simplicity. Indeed, orthodox quantum kinetics would seem to say little about mesoscopics that has not been revealed - nearly effortlessly - by more popular means. Such is far from the case, however. The fact that kinetic theory remains very much in charge is best appreciated through the physics of a quantum point contact. While discretization of its conductance is viewed as the exclusive result of coherent, single-electron-wave transmission, this does not begin to address the paramount feature of all metallic conduction: dissipation. A perfect quantum point contact still has finite resistance, so its ballistic carriers must dissipate the energy gained from the applied field. How do they manage that? The key is in standard many-body quantum theory, and its conservation principles.