# General parameter-shift rules for quantum gradients

@inproceedings{Wierichs2021GeneralPR, title={General parameter-shift rules for quantum gradients}, author={David Alexander Wierichs and Josh A. Izaac and Cody Wang and Cedric Yen-Yu Lin}, year={2021} }

Variational quantum algorithms are ubiquitous in applications of noisy intermediatescale quantum computers. Due to the structure of conventional parametrized quantum gates, the evaluated functions typically are finite Fourier series of the input parameters. In this work, we use this fact to derive new, general parameter-shift rules for single-parameter gates, and provide closed-form expressions to apply them. These rules are then extended to multi-parameter quantum gates by combining them with… Expand

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