Exchange interaction in gate-defined quantum dots beyond the Hubbard model
Mesoscale and Nanoscale Physics
2025-12-01 v1 Quantum Physics
Abstract
A quantitative description of the exchange interaction in quantum dots is relevant for modeling gate operations of spin qubits. By measuring the amplitude and frequency of exchange-driven qubit state oscillations, we measure the detuning dependence of the exchange coupling in a GaAs double quantum dot over three orders of magnitude. Both 1D and 3D full configuration interaction simulations can replicate the observed behavior. Extending a Hubbard model by including excited states increases the range of detuning where it provides a good fit, thus elucidating the underlying physics.
Cite
@article{arxiv.2511.23277,
title = {Exchange interaction in gate-defined quantum dots beyond the Hubbard model},
author = {Alexander Willmes and Patrick Bethke and M. Mohamed El Kordy Shehata and George Simion and M. A. Wolfe and Tim Botzem and Robert P. G. McNeil and Julian Ritzmann and Arne Ludwig and Andreas D. Wieck and Dieter Schuh and Dominique Bougeard and Hendrik Bluhm},
journal= {arXiv preprint arXiv:2511.23277},
year = {2025}
}
Comments
11 pages, 8 figures