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arXiv · 2210.11281

Doubling the order of approximation via the randomized product formula

Chien Hung Cho·Dominic W. Berry·Min-Hsiu Hsieh
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Abstract

Randomization has been applied to Hamiltonian simulation in a number of ways to improve the accuracy or efficiency of product formulas. Deterministic product formulas are often constructed in a symmetric way to provide accuracy of even order 2k. We show that by applying randomized corrections, it is possible to more than double the order to 4k + 1 (corresponding to a doubling of the order of the error). In practice, applying the corrections in a quantum algorithm requires some structure to the Hamiltonian, for example the Pauli strings as are used in the simulation of quantum chemistry.

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Chien Hung Cho, Dominic W. Berry, Min-Hsiu Hsieh. 2022-10-20. Doubling the order of approximation via the randomized product formula. https://doi.org/10.1103/physreva.109.062431

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