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arXiv · 2109.04962

Polynomial scaling enhancement in ground-state preparation of Ising spin models via counter-diabatic driving

Andreas Hartmann·Glen Bigan Mbeng·Wolfgang Lechner
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Abstract

The preparation of ground states of spin systems is a fundamental operation in quantum computing and serves as the basis of adiabatic quantum computing. This form of quantum computation is subject to the adiabatic theorem which in turn poses a fundamental speed limit. We show that by employing diabatic transitions via counter diabatic driving a less strict requirement on adiabaticity applies. We demonstrate a scaling advantage from local and multi-spin counter diabatic driving in the ground-state fidelity compared to their adiabatic counterpart, for different Ising spin models.

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Andreas Hartmann, Glen Bigan Mbeng, Wolfgang Lechner. 2021-09-10. Polynomial scaling enhancement in ground-state preparation of Ising spin models via counter-diabatic driving. https://doi.org/10.1103/physreva.105.022614

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