Complete Active Space Methods for NISQ Devices : The Importance of Canonical Orbital Optimization for Accuracy and Noise Resilience
De Gracia Triviño, Juan Angel ; Delcey, Mickael G. LU
and Wendin, Göran
(2023)
In Journal of Chemical Theory and Computation
19(10).
p.2863-2872
- Abstract
To avoid the scaling of the number of qubits with the size of the basis set, one can divide the molecular space into active and inactive regions, which is also known as complete active space methods. However, selecting the active space alone is not enough to accurately describe quantum mechanical effects such as correlation. This study emphasizes the importance of optimizing the active space orbitals to describe correlation and improve the basis-dependent Hartree-Fock energies. We will explore classical and quantum computation methods for orbital optimization and compare the chemically inspired ansatz, UCCSD, with the classical full CI approach for describing the active space in both weakly and strongly correlated molecules. Finally, we... (More)
To avoid the scaling of the number of qubits with the size of the basis set, one can divide the molecular space into active and inactive regions, which is also known as complete active space methods. However, selecting the active space alone is not enough to accurately describe quantum mechanical effects such as correlation. This study emphasizes the importance of optimizing the active space orbitals to describe correlation and improve the basis-dependent Hartree-Fock energies. We will explore classical and quantum computation methods for orbital optimization and compare the chemically inspired ansatz, UCCSD, with the classical full CI approach for describing the active space in both weakly and strongly correlated molecules. Finally, we will investigate the practical implementation of a quantum CASSCF, where hardware-efficient circuits must be used and noise can interfere with accuracy and convergence. Additionally, we will examine the impact of using canonical and noncanonical active orbitals on the convergence of the quantum CASSCF routine in the presence of noise.
(Less)
- author
- De Gracia Triviño, Juan Angel
; Delcey, Mickael G.
LU
and Wendin, Göran
- organization
- publishing date
- 2023-05-23
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of Chemical Theory and Computation
- volume
- 19
- issue
- 10
- pages
- 10 pages
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- pmid:37103120
- scopus:85156259803
- ISSN
- 1549-9618
- DOI
- 10.1021/acs.jctc.3c00123
- language
- English
- LU publication?
- yes
- id
- 70cd0a9e-7b40-4603-b043-ae006dae40f9
- date added to LUP
- 2023-08-16 12:38:39
- date last changed
- 2024-04-20 01:44:13
@article{70cd0a9e-7b40-4603-b043-ae006dae40f9,
abstract = {{<p>To avoid the scaling of the number of qubits with the size of the basis set, one can divide the molecular space into active and inactive regions, which is also known as complete active space methods. However, selecting the active space alone is not enough to accurately describe quantum mechanical effects such as correlation. This study emphasizes the importance of optimizing the active space orbitals to describe correlation and improve the basis-dependent Hartree-Fock energies. We will explore classical and quantum computation methods for orbital optimization and compare the chemically inspired ansatz, UCCSD, with the classical full CI approach for describing the active space in both weakly and strongly correlated molecules. Finally, we will investigate the practical implementation of a quantum CASSCF, where hardware-efficient circuits must be used and noise can interfere with accuracy and convergence. Additionally, we will examine the impact of using canonical and noncanonical active orbitals on the convergence of the quantum CASSCF routine in the presence of noise.</p>}},
author = {{De Gracia Triviño, Juan Angel and Delcey, Mickael G. and Wendin, Göran}},
issn = {{1549-9618}},
language = {{eng}},
month = {{05}},
number = {{10}},
pages = {{2863--2872}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Journal of Chemical Theory and Computation}},
title = {{Complete Active Space Methods for NISQ Devices : The Importance of Canonical Orbital Optimization for Accuracy and Noise Resilience}},
url = {{http://dx.doi.org/10.1021/acs.jctc.3c00123}},
doi = {{10.1021/acs.jctc.3c00123}},
volume = {{19}},
year = {{2023}},
}