We investigate automated in situ optimization of the potential landscape in a quantum point contact device, using a 3×3 gate array patterned atop the constriction. Optimization is performed using the covariance matrix adaptation evolutionary strategy, for which we introduce a metric for how "step-like" the conductance is as the channel becomes constricted. We first perform the optimization of the gate voltages in a tight-binding simulation and show how such in situ tuning can be used to mitigate a random disorder potential. The optimization is then performed in a physical device in experiment, where we also observe a marked improvement in the quantization of the conductance resulting from the optimization procedure.
@article{arxiv.2412.04997,
title = {Automated in situ optimization and disorder mitigation in a quantum device},
author = {Jacob Benestad and Torbjørn Rasmussen and Bertram Brovang and Oswin Krause and Saeed Fallahi and Geoffrey C. Gardner and Michael J. Manfra and Charles M. Marcus and Jeroen Danon and Ferdinand Kuemmeth and Anasua Chatterjee and Evert van Nieuwenburg},
journal= {arXiv preprint arXiv:2412.04997},
year = {2026}
}