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arXiv · 2401.10321

Doubling Efficiency of Hamiltonian Simulation via Generalized Quantum Signal Processing

Dominic W. Berry·Danial Motlagh·Giacomo Pantaleoni·Nathan Wiebe
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Abstract

Quantum signal processing provides an optimal procedure for simulating Hamiltonian evolution on a quantum computer using calls to a block encoding of the Hamiltonian. In many situations it is possible to control between forward and reverse steps with almost identical cost to a simple controlled operation. We show that it is then possible to reduce the cost of Hamiltonian simulation by a factor of 2 using the recent results of generalised quantum signal processing.

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Dominic W. Berry, Danial Motlagh, Giacomo Pantaleoni, Nathan Wiebe. 2024-01-18. Doubling Efficiency of Hamiltonian Simulation via Generalized Quantum Signal Processing. https://doi.org/10.1103/physreva.110.012612

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