Variational quantum eigensolver techniques for simulating carbon monoxide oxidation

TL;DR

This paper advances adaptive variational quantum algorithms to efficiently simulate molecules involved in carbon monoxide oxidation, reducing measurement overhead and demonstrating potential for practical chemical problem-solving on NISQ devices.

Contribution

It introduces a method to decrease measurement overhead in ADAPT-VQE by adding multiple operators per step, enabling simulation of larger molecules like O₂, CO, and CO₂.

Findings

Successful simulation of CO oxidation molecules using the proposed method

Reduced measurement overhead compared to traditional ADAPT-VQE

Energy estimates align with classical and VQE-UCCSD results

Abstract

A family of Variational Quantum Eigensolver (VQE) methods is designed to maximize the resource of existing noisy intermediate-scale quantum (NISQ) devices. However, VQE approaches encounter various difficulties in simulating molecules of industrially relevant sizes, among which the choice of the ansatz for the molecular wavefunction plays a crucial role. In this work, we push forward the capabilities of adaptive variational algorithms (ADAPT-VQE) by demonstrating that the measurement overhead can be significantly reduced via adding multiple operators at each step while keeping the ansatz compact. Within the proposed approach, we simulate a set of molecules, O$_2$, CO, and CO$_2$, participating in the carbon monoxide oxidation processes using the statevector simulator and compare our findings with the results obtained using VQE-UCCSD and classical methods. Based on these results, we estimate the energy characteristics of the chemical reaction. Our results pave the way to the use of variational approaches for solving practically relevant chemical problems.