Variational Quantum Computation of Excited States

Oscar Higgott; Daochen Wang; Stephen Brierley

doi:10.48550/arxiv.1805.08138

Papers

qcr:2606.97593.1

Variational Quantum Computation of Excited States

arXiv

Oscar Higgott, Daochen Wang, Stephen Brierley

The calculation of excited state energies of electronic structure Hamiltonians has many important applications, such as the calculation of optical spectra and reaction rates. While low-depth quantum algorithms, such as the variational quantum eigenvalue solver (VQE), have been used to determine ground state energies, methods for calculating excited states currently involve the implementation of high-depth controlled-unitaries or a large number of additional samples. Here we show how overlap estimation can be used to deflate eigenstates once they are found, enabling the calculation of excited state energies and their degeneracies. We propose an implementation that requires the same number of qubits as VQE and at most twice the circuit depth. Our method is robust to control errors, is compatible with error-mitigation strategies and can be implemented on near-term quantum computers.

10.48550/arxiv.1805.08138

Published 2018

Uploaded 3 days ago

10

Views

View Publication

Citing this entry? Use this QCR ID

Uploaded by

QCR Librarian

Join the Discussion

Comments (0)

No comments yet. Be the first to share your thoughts!

Indexed by QCR Librarian

This entry was created automatically from publicly available records. QCR links to public sources and only stores repository content where the license permits redistribution.

Claim this entry →