The Cost of Improving the Precision of the Variational Quantum Eigensolver for Quantum Chemistry

0553532 - ÚFM 2023 RIV CH eng J - Článek v odborném periodiku
Miháliková, Ivana - Pivoluska, M. - Plesch, M. - Friák, Martin - Nagaj, D. - Šob, Mojmír
The Cost of Improving the Precision of the Variational Quantum Eigensolver for Quantum Chemistry.
Nanomaterials. Roč. 12, č. 2 (2022), č. článku 243. E-ISSN 2079-4991
Institucionální podpora: RVO:68081723
Klíčová slova: optimization * noisy quantum processors * variational quantum eigensolver * quantum chemistry
Obor OECD: Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect)
Impakt faktor: 5.3, rok: 2022
Způsob publikování: Open access
https://www.mdpi.com/2079-4991/12/2/243

New approaches into computational quantum chemistry can be developed through the use of quantum computing. While universal, fault-tolerant quantum computers are still not available, and we want to utilize today's noisy quantum processors. One of their flagship applications is the variational quantum eigensolver (VQE)-an algorithm for calculating the minimum energy of a physical Hamiltonian. In this study, we investigate how various types of errors affect the VQE and how to efficiently use the available resources to produce precise computational results. We utilize a simulator of a noisy quantum device, an exact statevector simulator, and physical quantum hardware to study the VQE algorithm for molecular hydrogen. We find that the optimal method of running the hybrid classical-quantum optimization is to: (i) allow some noise in intermediate energy evaluations, using fewer shots per step and fewer optimization iterations, but ensure a high final readout precision, (ii) emphasize efficient problem encoding and ansatz parametrization, and (iii) run all experiments within a short time-frame, avoiding parameter drift with time. Nevertheless, current publicly available quantum resources are still very noisy and scarce/expensive, and even when using them efficiently, it is quite difficult to perform trustworthy calculations of molecular energies.
Trvalý link: http://hdl.handle.net/11104/0330857