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Higher Order Methods for Simulations on Quantum Computers

A. T. Sornborger·E. D. Stewart
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Abstract

To efficiently implement many-qubit gates for use in quantum simulations on quantum computers we develop and present methods reexpressing exp[-i (H_1 + H_2 + ...) Δt] as a product of factors exp[-i H_1 Δt], exp[-i H_2 Δt], ... which is accurate to 3rd or 4th order in Δt. The methods we derive are an extended form of symplectic method and can also be used for the integration of classical Hamiltonians on classical computers. We derive both integral and irrational methods, and find the most efficient methods in both cases.

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A. T. Sornborger, E. D. Stewart. 1999-03-15. Higher Order Methods for Simulations on Quantum Computers. https://doi.org/10.1103/physreva.60.1956

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