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arXiv · 2412.08719

Short-time simulation of quantum dynamics by Pauli measurements

Paul K. Faehrmann·Jens Eisert·Maria Kieferova·Richard Kueng
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Abstract

Simulating the dynamics of complex quantum systems is a central application of quantum devices. Here, we propose leveraging the power of measurements to simulate short-time quantum dynamics of physically prepared quantum states in classical post-processing using a truncated Taylor series approach. While limited to short simulation times, our hybrid quantum-classical method is equipped with rigorous error bounds. It is extendable to estimate low-order Taylor approximations of smooth, time-dependent functions of tractable linear combinations of measurable operators. These insights can be made use of in the context of Hamiltonian learning and device verification, short-time imaginary time evolution, or the application of intractable operations to sub-universal quantum simulators in classical post-processing.

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Paul K. Faehrmann, Jens Eisert, Maria Kieferova, Richard Kueng. 2025-05-15. Short-time simulation of quantum dynamics by Pauli measurements. https://doi.org/10.1103/6ggs-y392

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