Single-electron heat diode

TL;DR

This paper introduces a nanoscale single-electron heat diode that allows heat flow in one direction via electron fluctuations, while blocking it in the reverse, using quantum dots and Coulomb blockade effects.

Contribution

The paper presents the design and theoretical analysis of a novel single-electron heat diode utilizing quantum dots and capacitive coupling for directional heat transfer.

Findings

Heat flow is enabled in the forward direction by a four-step tunneling cycle.

Reverse heat flow is suppressed by Coulomb blockade, reducing leakage.

Optimal setup achieves reverse heat current only a few percent of the forward current.

Abstract

We introduce a new functional nanoscale device, a single-electron heat diode, consisting of two quantum dots or metallic islands coupled to electronic reservoirs by tunnel contacts. Electron transport through the system is forbidden but the capacitive coupling between the two dots allows electronic fluctuations to transmit heat between the reservoirs. When the reservoir temperatures are biased in the forward direction, heat flow is enabled by a four-step sequential tunneling cycle, while in the reverse-biased configuration this process is suppressed due to Coulomb blockade effects. In an optimal setup the leakage heat current in the reverse direction is only a few percent of the forward current.