Quantum Orbital Minimization Method for Excited States Calculation on a Quantum Computer.

Journal Article (Journal Article)

We propose a quantum-classical hybrid variational algorithm, the quantum orbital minimization method (qOMM), for obtaining the ground state and low-lying excited states of a Hermitian operator. Given parametrized ansatz circuits representing eigenstates, qOMM implements quantum circuits to represent the objective function in the orbital minimization method and adopts a classical optimizer to minimize the objective function with respect to the parameters in ansatz circuits. The objective function has an orthogonality constraint implicitly embedded, which allows qOMM to apply a different ansatz circuit to each input reference state. We carry out numerical simulations that seek to find excited states of H2 , LiH, and a toy model consisting of four hydrogen atoms arranged in a square lattice in the STO-3G basis with UCCSD ansatz circuits. Comparing the numerical results with existing excited states methods, qOMM is less prone to getting stuck in local minima and can achieve convergence with more shallow ansatz circuits.

Full Text

Duke Authors

Cited Authors

  • Bierman, J; Li, Y; Lu, J

Published Date

  • August 2022

Published In

Volume / Issue

  • 18 / 8

Start / End Page

  • 4674 - 4689

PubMed ID

  • 35876650

Electronic International Standard Serial Number (EISSN)

  • 1549-9626

International Standard Serial Number (ISSN)

  • 1549-9618

Digital Object Identifier (DOI)

  • 10.1021/acs.jctc.2c00218

Language

  • eng