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arXiv · 1908.06283

Push-Pull Optimization of Quantum Controls

Priya Batra·V. R. Krithika·T. S. Mahesh
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Abstract

Quantum optimal control involves setting up an objective function that evaluates the quality of an operator representing the realized process w.r.t. the target process. Here we propose a stronger objective function which incorporates not only the target operator but also a set of its orthogonal operators. We find significantly superior convergence of optimization routines with the combined influences of all the operators. We refer to this method as the $\textit{push-pull}$ optimization. In particular, we describe adopting the push-pull optimization to a gradient based approach and a variational-principle based approach. We carry out extensive numerical simulations of the push-pull optimization of quantum controls on a pair of Ising coupled qubits. Finally, we demonstrate its experimental application by preparing a long-lived singlet-order in a two-qubit system using NMR techniques.

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Priya Batra, V. R. Krithika, T. S. Mahesh. 2019-08-17. Push-Pull Optimization of Quantum Controls. https://doi.org/10.1103/physrevresearch.2.013314

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