Energy Dependent Tunneling in a Quantum Dot

TL;DR

This paper investigates electron tunneling rates in a quantum dot, demonstrating their exponential dependence on bias and gate voltages, and models the process as elastic tunneling relative to barrier height.

Contribution

It provides a quantitative model of energy-dependent elastic tunneling in quantum dots based on measured tunneling rates and bias/voltage dependence.

Findings

Tunneling rates depend exponentially on bias and gate voltages.

Tunneling process is elastic, conserving energy.

A model accurately describes tunneling relative to barrier height.

Abstract

We present measurements of the rates for an electron to tunnel on and off a quantum dot, obtained using a quantum point contact charge sensor. The tunnel rates show exponential dependence on drain-source bias and plunger gate voltages. The tunneling process is shown to be elastic, and a model describing tunneling in terms of the dot energy relative to the height of the tunnel barrier quantitatively describes the measurements.