Imaging correlated wave functions of few-electron quantum dots: Theory and scanning tunneling spectroscopy experiments

TL;DR

This paper combines theoretical modeling and experimental scanning tunneling spectroscopy to reveal how electron-electron correlations influence the wave functions of few-electron quantum dots, providing detailed insights into their electronic structure.

Contribution

It introduces a comprehensive approach that integrates many-body tunneling theory with experimental STS data to analyze correlation effects in quantum dots.

Findings

Correlation effects significantly distort STS images of double-charged quantum dots.

Theoretical models accurately reproduce experimental wave function sequences.

Electron-electron interactions are crucial for understanding quantum dot electronic states.

Abstract

We show both theoretically and experimentally that scanning tunneling spectroscopy (STS) images of semiconductor quantum dots may display clear signatures of electron-electron correlation. We apply many-body tunneling theory to a realistic model which fully takes into account correlation effects and dot anisotropy. Comparing measured STS images of freestanding InAs quantum dots with those calculated by the full configuration interaction method, we explain the wave function sequence in terms of images of one- and two-electron states. The STS map corresponding to double charging is significantly distorted by electron correlation with respect to the non-interacting case.