---
_id: '33226'
abstract:
- lang: eng
  text: A parallel hybrid quantum-classical algorithm for the solution of the quantum-chemical
    ground-state energy problem on gate-based quantum computers is presented. This
    approach is based on the reduced density-matrix functional theory (RDMFT) formulation
    of the electronic structure problem. For that purpose, the density-matrix functional
    of the full system is decomposed into an indirectly coupled sum of density-matrix
    functionals for all its subsystems using the adaptive cluster approximation to
    RDMFT. The approximations involved in the decomposition and the adaptive cluster
    approximation itself can be systematically converged to the exact result. The
    solutions for the density-matrix functionals of the effective subsystems involves
    a constrained minimization over many-particle states that are approximated by
    parametrized trial states on the quantum computer similarly to the variational
    quantum eigensolver. The independence of the density-matrix functionals of the
    effective subsystems introduces a new level of parallelization and allows for
    the computational treatment of much larger molecules on a quantum computer with
    a given qubit count. In addition, for the proposed algorithm techniques are presented
    to reduce the qubit count, the number of quantum programs, as well as its depth.
    The evaluation of a density-matrix functional as the essential part of our approach
    is demonstrated for Hubbard-like systems on IBM quantum computers based on superconducting
    transmon qubits.
article_type: original
author:
- first_name: Robert
  full_name: Schade, Robert
  id: '75963'
  last_name: Schade
  orcid: 0000-0002-6268-539
- first_name: Carsten
  full_name: Bauer, Carsten
  id: '90082'
  last_name: Bauer
- first_name: Konstantin
  full_name: Tamoev, Konstantin
  id: '50177'
  last_name: Tamoev
- first_name: Lukas
  full_name: Mazur, Lukas
  id: '90492'
  last_name: Mazur
  orcid: ' 0000-0001-6304-7082'
- first_name: Christian
  full_name: Plessl, Christian
  id: '16153'
  last_name: Plessl
  orcid: 0000-0001-5728-9982
- first_name: Thomas
  full_name: Kühne, Thomas
  id: '49079'
  last_name: Kühne
citation:
  ama: Schade R, Bauer C, Tamoev K, Mazur L, Plessl C, Kühne T. Parallel quantum chemistry
    on noisy intermediate-scale quantum computers. <i>Phys Rev Research</i>. 2022;4:033160.
    doi:<a href="https://doi.org/10.1103/PhysRevResearch.4.033160">10.1103/PhysRevResearch.4.033160</a>
  apa: Schade, R., Bauer, C., Tamoev, K., Mazur, L., Plessl, C., &#38; Kühne, T. (2022).
    Parallel quantum chemistry on noisy intermediate-scale quantum computers. <i>Phys.
    Rev. Research</i>, <i>4</i>, 033160. <a href="https://doi.org/10.1103/PhysRevResearch.4.033160">https://doi.org/10.1103/PhysRevResearch.4.033160</a>
  bibtex: '@article{Schade_Bauer_Tamoev_Mazur_Plessl_Kühne_2022, title={Parallel quantum
    chemistry on noisy intermediate-scale quantum computers}, volume={4}, DOI={<a
    href="https://doi.org/10.1103/PhysRevResearch.4.033160">10.1103/PhysRevResearch.4.033160</a>},
    journal={Phys. Rev. Research}, publisher={American Physical Society}, author={Schade,
    Robert and Bauer, Carsten and Tamoev, Konstantin and Mazur, Lukas and Plessl,
    Christian and Kühne, Thomas}, year={2022}, pages={033160} }'
  chicago: 'Schade, Robert, Carsten Bauer, Konstantin Tamoev, Lukas Mazur, Christian
    Plessl, and Thomas Kühne. “Parallel Quantum Chemistry on Noisy Intermediate-Scale
    Quantum Computers.” <i>Phys. Rev. Research</i> 4 (2022): 033160. <a href="https://doi.org/10.1103/PhysRevResearch.4.033160">https://doi.org/10.1103/PhysRevResearch.4.033160</a>.'
  ieee: 'R. Schade, C. Bauer, K. Tamoev, L. Mazur, C. Plessl, and T. Kühne, “Parallel
    quantum chemistry on noisy intermediate-scale quantum computers,” <i>Phys. Rev.
    Research</i>, vol. 4, p. 033160, 2022, doi: <a href="https://doi.org/10.1103/PhysRevResearch.4.033160">10.1103/PhysRevResearch.4.033160</a>.'
  mla: Schade, Robert, et al. “Parallel Quantum Chemistry on Noisy Intermediate-Scale
    Quantum Computers.” <i>Phys. Rev. Research</i>, vol. 4, American Physical Society,
    2022, p. 033160, doi:<a href="https://doi.org/10.1103/PhysRevResearch.4.033160">10.1103/PhysRevResearch.4.033160</a>.
  short: R. Schade, C. Bauer, K. Tamoev, L. Mazur, C. Plessl, T. Kühne, Phys. Rev.
    Research 4 (2022) 033160.
date_created: 2022-08-29T14:07:01Z
date_updated: 2023-08-02T15:04:22Z
department:
- _id: '27'
- _id: '518'
doi: 10.1103/PhysRevResearch.4.033160
intvolume: '         4'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://journals.aps.org/prresearch/abstract/10.1103/PhysRevResearch.4.033160
oa: '1'
page: '033160'
project:
- _id: '52'
  name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing'
publication: Phys. Rev. Research
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
status: public
title: Parallel quantum chemistry on noisy intermediate-scale quantum computers
type: journal_article
user_id: '75963'
volume: 4
year: '2022'
...