Influence of confining potentials on the exchange coupling in double quantum dots

TL;DR

This paper derives simple formulas for exchange coupling in double quantum dots under various confining potentials, highlighting how potential details influence coupling at different distances and magnetic fields, aiding experimental and numerical modeling.

Contribution

It provides analytical expressions for exchange coupling considering four different potentials, clarifying the impact of potential features on quantum dot behavior.

Findings

Exchange coupling is insensitive to potential details at large distances and magnetic fields.

At low fields and short distances, potential features significantly affect exchange coupling.

Results serve as guidelines for numerical studies and experimental modeling.

Abstract

We report simple expressions for the exchange coupling in double quantum dots calculated within the Heitler-London and the Hund-Mulliken approximations using four different confining potentials. At large interdot distances and at large magnetic fields the exchange coupling does not depend significantly on the details of the potentials. In contrast, at low fields and short distances different behaviors of the exchange coupling can be attributed to particular features of the potentials. Our results may be useful as guidelines in numerical studies and in the modeling of experiments.