An Interface for Variational Quantum Eigensolver based Energy (VQE-E) and Force (VQE-F) Calculator to Atomic Simulation Environment (ASE)

TL;DR

This paper introduces a hybrid quantum-classical interface connecting VQE-based energy and force calculations with ASE, enabling efficient molecular geometry optimization and comparison with classical methods.

Contribution

It presents a novel interface integrating VQE-E and VQE-F quantum algorithms with ASE for improved molecular simulations.

Findings

Successfully optimized water molecule geometry using the interface.

Enables easy comparison and combination of quantum and classical methods.

Facilitates minimal coding effort for hybrid quantum-classical simulations.

Abstract

The development of quantum algorithms to solve quantum chemistry problems has offered a promising new paradigm of performing computer simulations at the scale of atoms and molecules. Although majority of the research so far has focused on designing quantum algorithms to compute ground and excited state energies and forces, it is useful to run different simulation tasks, such as geometry optimization, with these algorithms as subroutines. Towards this end, we have created an interface for the Variational Quantum Eigensolver based molecular Energy (VQE-E) and molecular Force (VQE-F) code to the Atomic Simulation Environment (ASE). We demonstrate the working of this hybrid quantum-classical interface by optimizing the geometry of water molecule using a native optimizer implemented in ASE. Furthermore, this interface enables one to compare, combine and use quantum algorithms in conjunction with related classical methods quite easily with minimal coding effort.