Linear-Scaling Quantum Circuits for Computational Chemistry

• Type of Material: Article
• Authors: Ilias Magoulas, Emory University; Francesco A. Evangelista, Emory University
• Language: English
• Date: 2023-07-06
• Publisher: American Chemical Society
• Publication Version: Final Published Version
• Copyright Statement: © 2023 The Authors.
• License: Creative Commons Attribution 4.0 International
• Final Published Version (URL): https://doi.org/10.1021/acs.jctc.3c00376
• Title of Journal or Parent Work: Journal of Chemical Theory and Computation
• Volume: 19
• Issue: 15
• Start Page: 4815
• End Page: 4821
• Grant/Funding Agency: U.S. Department of Energy
• Grant/Funding Information: This work is supported by the U.S. Department of Energy under Award No. DE-SC0019374.
• Keywords: Linear-Scaling Quantum Circuits; CNOT-efficient
• Subject - Topics: Computational chemistry

Abstract

We have recently constructed compact, CNOT-efficient, quantum circuits for Fermionic and qubit excitations of arbitrary many-body rank [Magoulas, I.; Evangelista, F. A. J. Chem. Theory Comput. 2023, 19, 822.]. Here, we present approximations of these circuits that substantially reduce the CNOT counts even further. Our preliminary numerical data, using the selected projective quantum eigensolver approach, show up to a 4-fold reduction in CNOTs. At the same time, there is practically no loss of accuracy in the energies compared to the parent implementation, while the ensuing symmetry breaking is essentially negligible.