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arXiv · 2006.00935

Hessian-based optimization of constrained quantum control

Mogens Dalgaard·Felix Motzoi·Jesper Hasseriis Mohr Jensen·Jacob Sherson
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Abstract

Efficient optimization of quantum systems is a necessity for reaching fault tolerant thresholds. A standard tool for optimizing simulated quantum dynamics is the gradient-based \textsc{grape} algorithm, which has been successfully applied in a wide range of different branches of quantum physics. In this work, we derive and implement exact $2^{\mathrm{nd}}$ order analytical derivatives of the coherent dynamics and find improvements compared to the standard of optimizing with the approximate $2^{\mathrm{nd}}$ order \textsc{bfgs}. We demonstrate performance improvements for both the best and average errors of constrained unitary gate synthesis on a circuit-\textsc{qed} system over a broad range of different gate durations.

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Mogens Dalgaard, Felix Motzoi, Jesper Hasseriis Mohr Jensen, Jacob Sherson. 2020-06-01. Hessian-based optimization of constrained quantum control. https://doi.org/10.1103/physreva.102.042612

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