Phonon assisted resonant tunnelling and its phonons control

TL;DR

This paper investigates how phonons influence resonant tunnelling in InAs quantum dots, revealing sharp conductance features linked to phonon modes and proposing a model to describe these effects for better nano-device control.

Contribution

It introduces a quasi-classical model showing how phonons affect resonant tunnelling in quantum dots, highlighting phonon control in nano-electronic device characteristics.

Findings

Resonant features in conductance are linked to phonon modes.

A solvable model describes tunnelling with phonon interactions.

Device characteristics can be controlled via phonon properties.

Abstract

We observe a series of sharp resonant features in the tunnelling differential conductance of InAs quantum dots. We found that dissipative quantum tunnelling has a strong influence on the operation of nano-devices. Because of such tunnelling the current-voltage characteristics of tunnel contact created between atomic force microscope tip and a surface of InAs/GaAs quantum dots display many interesting peaks. We found that the number, position, and heights of these peaks are associated with the phonon modes involved. To describe the found effect we use a quasi-classical approximation. There the tunnelling current is related to a creation of a dilute instanton-anti-instanton gas. Our experimental data are well described with exactly solvable model where one charged particle is weakly interacting with two promoting phonon modes associated with external medium. We conclude that the characteristics of the tunnel nanoelectronic devices can thus be controlled by a proper choice of phonons existing in materials, which are involved.