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arXiv · 2301.11838

Quantum-enhanced quantum Monte Carlo: an industrial view

Maximilian Amsler·Peter Deglmann·Matthias Degroote·Michael P. Kaicher·Matthew Kiser·Michael Kühn·Chandan Kumar·Andreas Maier·Georgy Samsonidze·Anna Schroeder·Michael Streif·Davide Vodola·Christopher Wever
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Abstract

In this work, we test a recently developed method to enhance classical auxiliary-field quantum Monte Carlo (AFQMC) calculations with quantum computers against examples from chemistry and material science, representatives of classes of industry-relevant systems. As molecular test cases, we calculate the energy curve of H4 and relative energies of ozone and singlet molecular oxygen with respect to triplet molecular oxygen, which are industrially relevant in organic oxidation reactions. We find that trial wave functions beyond single Slater determinants improve the performance of AFQMC and allow to generate energies close to chemical accuracy compared to full configuration interaction (FCI) or experimental results. As a representative for material science we study a quasi-1D Fermi-Hubbard model derived from CuBr2, a compound displaying electronic structure properties analogous to cuprates. We find that trial wave functions with both, significantly larger fidelities and lower energies over a Hartree-Fock solution, do not necessarily lead to better AFQMC results.

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Maximilian Amsler, Peter Deglmann, Matthias Degroote, Michael P. Kaicher, Matthew Kiser, Michael Kühn, Chandan Kumar, Andreas Maier, Georgy Samsonidze, Anna Schroeder, Michael Streif, Davide Vodola, Christopher Wever. 2023-01-27. Quantum-enhanced quantum Monte Carlo: an industrial view. https://arxiv.org/abs/2301.11838

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