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arXiv · 2508.09024

Automated Charge Transition Detection in Quantum Dot Charge Stability Diagrams

Fabian Hader·Fabian Fuchs·Sarah Fleitmann·Karin Havemann·Benedikt Scherer·Jan Vogelbruch·Lotte Geck·Stefan van Waasen
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Abstract

Gate-defined semiconductor quantum dots require an appropriate number of electrons to function as qubits. The number of electrons is usually tuned by analyzing charge stability diagrams, in which charge transitions manifest as edges. Therefore, to fully automate qubit tuning, it is necessary to recognize these edges automatically and reliably. This paper investigates possible detection methods, describes their training with simulated data from the SimCATS framework, and performs a quantitative comparison with a future hardware implementation in mind. Furthermore, we investigated the quality of the optimized approaches on experimentally measured data from a GaAs and a SiGe qubit sample.

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Fabian Hader, Fabian Fuchs, Sarah Fleitmann, Karin Havemann, Benedikt Scherer, Jan Vogelbruch, Lotte Geck, Stefan van Waasen. 2025-08-12. Automated Charge Transition Detection in Quantum Dot Charge Stability Diagrams. https://doi.org/10.1109/tqe.2025.3596392

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