Heat and charge transport measurements to access single‐electron quantum characteristics

Abstract

In the framework of the Floquet scattering‐matrix theory, we discuss how electrical and heat currents accessible in mesoscopics are related to the state of excitations injected by a single‐electron source into an electron waveguide. We put forward an interpretation of a single‐particle heat current, which differs essentially from that of an electrical current. We show that the knowledge of both a time‐dependent electrical current and a time‐dependent heat current allows the full reconstruction of a single‐electron wave function. In addition, we compare electrical and heat shot noise caused by splitting of a regular stream of single‐electron excitations. If only one stream impinges on a wave splitter, the heat shot noise is proportional to the well‐known expression of the charge shot noise, reflecting the partitioning of the incoming single particles. The situation differs when two electronic streams collide at the wave splitter. The shot noise suppression, due to the Pauli exclusion principle, is governed by different overlap integrals in the case of charge and of heat.