Robust optimal control of interacting multi-qubit systems for quantum sensing

Nguyen H. Le; Max Cykiert; Eran Ginossar

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arXiv · 2110.12560

Robust optimal control of interacting multi-qubit systems for quantum sensing

Nguyen H. Le·Max Cykiert·Eran Ginossar

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Abstract

Realising high fidelity entangled states in controlled quantum many-body systems is challenging due to experimental uncertainty in a large number of physical quantities. We develop a robust optimal control method for achieving this goal in finite-size multi-qubit systems despite significant uncertainty in multiple parameters. We demonstrate its effectiveness in the generation of the Greenberger-Horne-Zeilinger state on a star graph of capacitively coupled transmons, and discuss its crucial role for achieving the Heisenberg limit of precision in quantum sensing.

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Nguyen H. Le, Max Cykiert, Eran Ginossar. 2021-10-25. Robust optimal control of interacting multi-qubit systems for quantum sensing. https://arxiv.org/abs/2110.12560

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