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Stellarator Coils for Future Fusion Reactors via an Augmented Lagrangian Approach

Pedro F. Gil1, Weiping Li2,3, Julianne Stratton3, Alan A. Kaptanoglu3, and Eve V. Stenson1

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Phys. Rev. Lett. 137, 065101 – Published 7 August, 2026

DOI: https://doi.org/10.1103/n7gk-922h

Abstract

A long-standing issue for fusion reactors based on 3D magnetic confinement (stellarators) has been finding suitable coils. Traditional optimization methods struggle to balance multiple physics and engineering constraints, requiring significant computing resources and input tuning, yet still resulting in suboptimal or infeasible configurations. We present a new optimization method based on an augmented Lagrangian scheme and show that it efficiently generates stellarator coils that exhibit enhanced physics performance and meet essential design requirements. This will accelerate progress toward commercially viable stellarator fusion reactors.

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Efficient computation of stellarator coils with an augmented Lagrangian optimization method

Pedro F. Gil, Weiping Li, Julianne Stratton, Alan A. Kaptanoglu, and Eve V. Stenson
Phys. Rev. E 114, 025202 (2026)

Article Text

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Phys. Rev. Lett. 137, 065101– Published 7 August, 2026
  • Received 10 October 2025
  • Accepted 10 July 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Open access publication funded by the Max Planck Society.

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