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arXiv · 2510.04798

Finite elements and moving asymptotes accelerate quantum optimal control -- FEMMA

Mengjia He·Yongbo Deng·Burkhard Luy·Jan G. Korvink
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Abstract

Quantum optimal control is central to designing spin manipulation pulses. Gradient-based pulse optimization can be facilitated by either accelerating gradient evaluation or enhancing the convergence rate. In this work, we accelerated single-spin optimal control by combining the finite element method with the method of moving asymptotes. By treating discretized time as spatial coordinates, the Liouville - von Neumann equation was reformulated as a linear system, efficiently yielding a joint solution of the spin trajectory and control gradient. The method of moving asymptotes, relying on the ensemble fidelities and gradients, achieves rapid convergence for a target fidelity of 0.995.

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Mengjia He, Yongbo Deng, Burkhard Luy, Jan G. Korvink. 2025-10-06. Finite elements and moving asymptotes accelerate quantum optimal control -- FEMMA. https://doi.org/10.1063/5.0305310

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