Toward prethreshold gatebased quantum simulation of chemical dynamics: using potential energy surfaces to simulate fewchannel molecular collisions
Here, one of the most promising applications of an errorcorrected universal quantum computer is the efficient simulation of complex quantum systems such as large molecular systems. In this application, one is interested in both the electronic structure such as the ground state energy and dynamical properties such as the scattering cross section and chemical reaction rates. However, most theoretical work and experimental demonstrations have focused on the quantum computation of energies and energy surfaces. In this work, we attempt to make the prethreshold (not errorcorrected) quantum simulation of dynamical properties practical as well. We show that the use of precomputed potential energy surfaces and couplings enables the gatebased simulation of fewchannel but otherwise realistic molecular collisions. Our approach is based on the widely used Born–Oppenheimer approximation for the structure problem coupled with a semiclassical method for the dynamics. In the latter the electrons are treated quantum mechanically but the nuclei are classical, which restricts the collisions to high energy or temperature (typically above ≈10 eV). By using operator splitting techniques optimized for the resulting timedependent Hamiltonian simulation problem, we give several physically realistic collision examples, with 3–8 channels and circuit depths < 1000.
 Authors:

^{[1]}
;
^{[2]};
^{[2]}
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Univ. of Georgia, Athens, GA (United States)
 Publication Date:
 Report Number(s):
 LAUR1821819
Journal ID: ISSN 15700755
 Grant/Contract Number:
 AC5206NA25396
 Type:
 Accepted Manuscript
 Journal Name:
 Quantum Information Processing
 Additional Journal Information:
 Journal Volume: 17; Journal Issue: 5; Journal ID: ISSN 15700755
 Publisher:
 Springer
 Research Org:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Sponsoring Org:
 USDOE
 Country of Publication:
 United States
 Language:
 English
 Subject:
 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Computer Science; Inorganic and Physical Chemistry; Mathematics
 OSTI Identifier:
 1435540
Sornborger, Andrew Tyler, Stancil, Phillip, and Geller, Michael R. Toward prethreshold gatebased quantum simulation of chemical dynamics: using potential energy surfaces to simulate fewchannel molecular collisions. United States: N. p.,
Web. doi:10.1007/s111280181878x.
Sornborger, Andrew Tyler, Stancil, Phillip, & Geller, Michael R. Toward prethreshold gatebased quantum simulation of chemical dynamics: using potential energy surfaces to simulate fewchannel molecular collisions. United States. doi:10.1007/s111280181878x.
Sornborger, Andrew Tyler, Stancil, Phillip, and Geller, Michael R. 2018.
"Toward prethreshold gatebased quantum simulation of chemical dynamics: using potential energy surfaces to simulate fewchannel molecular collisions". United States.
doi:10.1007/s111280181878x.
@article{osti_1435540,
title = {Toward prethreshold gatebased quantum simulation of chemical dynamics: using potential energy surfaces to simulate fewchannel molecular collisions},
author = {Sornborger, Andrew Tyler and Stancil, Phillip and Geller, Michael R.},
abstractNote = {Here, one of the most promising applications of an errorcorrected universal quantum computer is the efficient simulation of complex quantum systems such as large molecular systems. In this application, one is interested in both the electronic structure such as the ground state energy and dynamical properties such as the scattering cross section and chemical reaction rates. However, most theoretical work and experimental demonstrations have focused on the quantum computation of energies and energy surfaces. In this work, we attempt to make the prethreshold (not errorcorrected) quantum simulation of dynamical properties practical as well. We show that the use of precomputed potential energy surfaces and couplings enables the gatebased simulation of fewchannel but otherwise realistic molecular collisions. Our approach is based on the widely used Born–Oppenheimer approximation for the structure problem coupled with a semiclassical method for the dynamics. In the latter the electrons are treated quantum mechanically but the nuclei are classical, which restricts the collisions to high energy or temperature (typically above ≈10 eV). By using operator splitting techniques optimized for the resulting timedependent Hamiltonian simulation problem, we give several physically realistic collision examples, with 3–8 channels and circuit depths < 1000.},
doi = {10.1007/s111280181878x},
journal = {Quantum Information Processing},
number = 5,
volume = 17,
place = {United States},
year = {2018},
month = {3}
}