Validity of the single-particle description and charge noise resilience for multielectron quantum dots

TL;DR

This paper constructs optimal single-particle states for multielectron quantum dots using natural orbitals, demonstrating that four-electron quantum dots are more resilient to charge noise than two-electron dots, with implications for quantum computing.

Contribution

It introduces a method to include Coulomb effects in single-particle states of quantum dots using natural orbitals, showing improved noise resilience in multielectron systems.

Findings

Natural orbitals agree with noninteracting orbitals for GaAs QDs

Coulomb interactions rescale the orbital radius

Four-electron QDs are less susceptible to charge noise

Abstract

We construct an optimal set of single-particle states for few-electron quantum dots (QDs) using the method of natural orbitals (NOs). The NOs include also the effects of the Coulomb repulsion between electrons. We find that they agree well with the noniteracting orbitals for GaAs QDs of realistic parameters, while the Coulomb interactions only rescale the radius of the NOs compared to the noninteracting case. We use NOs to show that four-electron QDs are less susceptible to charge noise than their two-electron counterparts.