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arXiv · 2206.09881

Near-term quantum algorithm for computing molecular and materials properties based on recursive variational series methods

Phillip W. K. Jensen·Peter D. Johnson·Alexander A. Kunitsa
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Abstract

Determining the properties of molecules and materials is one of the premier applications of quantum computing. A major question in the field is: how might we use imperfect near-term quantum computers to solve problems of practical value? We propose a quantum algorithm to estimate the properties of molecules using near-term quantum devices. The method is a recursive variational series estimation method, where we expand an operator of interest in terms of Chebyshev polynomials and evaluate each term in the expansion using a variational quantum algorithm. We test our method by computing the one-particle Green's function in the energy domain and the autocorrelation function in the time domain.

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Phillip W. K. Jensen, Peter D. Johnson, Alexander A. Kunitsa. 2022-06-20. Near-term quantum algorithm for computing molecular and materials properties based on recursive variational series methods. https://doi.org/10.1103/physreva.108.022422

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