Repository logo
 

Chemical Energy Landscapes of Hardware-Efficient Ansätze in Quantum Computing

Accepted version
Peer-reviewed

Change log

Authors

Boy, Choy 
Wales, David 

Abstract

Rapid advances in quantum computing have opened up new opportunities for solving the central electronic structure problem in computational chemistry. In the noisy intermediate-scale quantum (NISQ) era, where qubit coherence times are limited, it is essential to exploit quantum algorithms with sufficiently short quantum circuits to maximise qubit efficiency. The procedural construction of hardware-efficient ansätze provides one approach to design such circuits. However, refining the accuracy of the global minimum by increasing circuit depth may lead to a proliferation of local minima that hinder location of the global minimum. To investigate this phenomenon we explore the energy landscapes of hardware-efficient circuits to identify ground-state energies of the hydrogen, lithium hydride, and beryllium hydride molecules. We also propose a simple dimensionality reduction procedure that reduces quantum gate depth while retaining high accuracy for the global minimum, simplifying the energy landscape, and hence speeding up optimisation from both software and hardware perspectives.

Description

Keywords

Journal Title

Journal of Chemical Theory and Computation

Conference Name

Journal ISSN

1549-9618

Volume Title

Publisher

American Chemical Society

Publisher DOI

Publisher URL