Ionization energies in lithium and boron atoms using the Variational Quantum Eigensolver algorithm

TL;DR

This paper demonstrates the use of the Variational Quantum Eigensolver algorithm to compute ionization energies of lithium and boron atoms, extending its application beyond ground state energies in quantum chemistry.

Contribution

It introduces the calculation of ionization energies using VQE, showcasing its potential for broader property predictions in atomic systems.

Findings

Ionization energies computed with VQE show good agreement with classical results.

The method captures many-body trends in atomic properties.

VQE extends to properties beyond ground state energies.

Abstract

The classical-quantum hybrid Variational Quantum Eigensolver algorithm is the most widely used approach in the Noisy Intermediate Scale Quantum era to obtain ground state energies of atomic and molecular systems. In this work, we extend the scope of properties that can be calculated using the algorithm by computing the first ionization energies of Lithium and Boron atoms. We check the precision of our ionization energies and the observed many-body trends and compare them with the results from calculations carried out on traditional computers.