Excitation Spectra of Circular Few-Electron Quantum Dots

TL;DR

This paper investigates the excitation spectra of circular few-electron quantum dots, identifying quantum states and their transitions under magnetic fields, enabling atomic physics experiments in new regimes.

Contribution

It is the first study to identify quantum numbers of excited states in quantum dots and compare them directly with exact calculations.

Findings

Quantum numbers of excited states identified

Magnetic field induces state transitions

Transitions include crossings, singlet-triplet, and spin polarization

Abstract

We study ground states and excited states in semiconductor quantum dots containing 1 to 12 electrons. For the first time, it is possible to identify the quantum numbers of the states in the excitation spectra and make a direct comparison to exact calculations. A magnetic field induces transitions between excited states and ground state. These transitions are discussed in terms of crossings between single-particle states, singlet-triplet transitions, spin polarization, and Hund's rule. Our impurity-free quantum dots allow for atomic physics experiments in magnetic field regimes not accessible for atoms.