Shell filling in non-linear magneto-tunneling spectroscopy of vertical quantum dots

TL;DR

This paper demonstrates that non-linear magneto-tunneling spectroscopy in vertical quantum dots can probe both ground and excited states, revealing a large resonant peak associated with higher excited states.

Contribution

It introduces a spectroscopic method using non-linear magneto-tunneling to analyze electronic states in vertical quantum dots, highlighting the detection of higher excited states.

Findings

Conduction at low bias probes ground and first excited states.

A large resonant peak indicates tunneling across higher excited states.

Spectroscopy provides detailed insight into quantum dot energy levels.

Abstract

We report on non-linear magneto-tunneling experiments carried out in single GaAs vertical quantum dots. We show that conduction at low voltage bias can be a spectroscopic tool for both the ground state and first excited states of few electrons on the dot. Increasing voltage a large resonant peak is observed and attributed to tunneling across the quasi-continuum of higher excited states.