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arXiv · 1903.01654

Novel Trotter formulas for digital quantum simulation

Yi-Xiang Liu·Jordan Hines·Zhi Li·Ashok Ajoy·Paola Cappellaro
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Abstract

Quantum simulation promises to address many challenges in fields ranging from quantum chemistry to material science, and high-energy physics, and could be implemented in noisy intermediate-scale quantum devices. A challenge in building good digital quantum simulators is the fidelity of the engineered dynamics given a finite set of elementary operations. Here we present a framework for optimizing the order of operations based on a geometric picture, thus abstracting from the operation details and achieving computational efficiency. Based on this geometric framework, we provide two alternative second-order Trotter expansions, one with optimal fidelity at a short time scale, and the second robust at a long time scale. Thanks to the improved fidelity at different time scale, the two expansions we introduce can form the basis for experimental-constrained digital quantum simulation.

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Yi-Xiang Liu, Jordan Hines, Zhi Li, Ashok Ajoy, Paola Cappellaro. 2019-03-05. Novel Trotter formulas for digital quantum simulation. https://doi.org/10.1103/physreva.102.010601

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