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arXiv · 1810.07905

Time-optimal Control of Independent Spin-1/2 Systems under Simultaneous Control

Yunlan Ji·Ji Bian·Min Jiang·Domenico D'Alessandro·Xinhua Peng
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Abstract

We derive the explicit solution of the problem of time-optimal control by a common magnetic fields for two independent spin-$\frac{1}{2}$ particles. Our approach is based on the Pontryagin Maximum Principle and a novel symmetry reduction technique. We experimentally implement the optimal control using zero-field nuclear magnetic resonance. This reveals an average gate error of $1\%$ and a $70 \%$ to $80$ $\%$ decrease in the experiment duration as compared to existing methods. This is the first analytical solution and experimental demonstration of time-optimal control in such a system and it provides a route to achieve time optimal control in more general quantum systems.

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Yunlan Ji, Ji Bian, Min Jiang, Domenico D'Alessandro, Xinhua Peng. 2018-10-18. Time-optimal Control of Independent Spin-1/2 Systems under Simultaneous Control. https://doi.org/10.1103/physreva.98.062108

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