Variational quantum eigensolver for approximate diagonalization of downfolded Hamiltonians using generalized unitary coupled cluster ansatz

0543571 - ÚFCH JH 2022 RIV GB eng J - Journal Article
Bauman, N. P. - Chládek, J. - Veis, Libor - Pittner, Jiří - Kowalski, K.
Variational quantum eigensolver for approximate diagonalization of downfolded Hamiltonians using generalized unitary coupled cluster ansatz.
Quantum Science and Technology. Roč. 6, JUN 2021 (2021), č. článku 034008. ISSN 2058-9565. E-ISSN 2058-9565
R&D Projects: GA MŠMT(CZ) LTAUSA17033
Institutional support: RVO:61388955
Keywords : quantum chemistry * variational quantum eigensolver * generalized unitary coupled clusters
OECD category: Physical chemistry
Impact factor: 6.568, year: 2021
Method of publishing: Limited access

In this paper, we discuss the utilization of variational quantum solver (VQE) and recently introduced generalized unitary coupled cluster (GUCC) formalism for the diagonalization of downfolded/effective Hamiltonians in active spaces. In addition to effective Hamiltonians defined by the downfolding of a subset of virtual orbitals we also consider their form defined by freezing core orbitals, which enables us to deal with larger systems. We also consider various solvers to identify solutions of the GUCC equations. We use N2, H2O, and C2H4, as benchmark systems to illustrate the performance of the combined framework.
Permanent Link: http://hdl.handle.net/11104/0320757