AGP-based unitary coupled cluster theory for quantum computers
Quantum Physics
2022-11-02 v2 Strongly Correlated Electrons
Chemical Physics
Abstract
Electronic structure methods typically benefit from symmetry breaking and restoration, specially in the strong correlation regime. The same goes for Ans\"atze on a quantum computer. We develop a unitary coupled cluster method on the antisymmetrized geminal power (AGP) -- a state formally equivalent to the number-projected Bardeen--Cooper--Schrieffer wavefunction. We demonstrate our method for the single-band Fermi--Hubbard Hamiltonian in one and two dimensions. We also explore post-selection as a state preparation step to obtain correlated AGP and prove that it scales no worse than in the number of measurements, thereby making it a less expensive alternative to gauge integration to restore particle number symmetry.
Keywords
Cite
@article{arxiv.2205.13420,
title = {AGP-based unitary coupled cluster theory for quantum computers},
author = {Armin Khamoshi and Guo P. Chen and Francesco A. Evangelista and Gustavo E. Scuseria},
journal= {arXiv preprint arXiv:2205.13420},
year = {2022}
}