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arXiv:1909.12250 · Physical Review Research

Calculation of the Green's function on near-term quantum computers

Suguru Endo, Iori Kurata, Yuya O. Nakagawa

Published Aug 20, 2020• 94 citations
arXivHTMLPDF

Abstract

The authors propose a method to calculate the Green's function on near-term quantum computers. The method enables the calculation of several physical properties of the system of interest on near-term quantum computers.
DOI
10.1103/physrevresearch.2.033281

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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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