Exploring non-linear correlators on AGP

Abstract

Single-reference methods such as Hartree-Fock-based coupled cluster theory are well known for their accuracy and efficiency for weakly correlated systems. For strongly correlated systems, more sophisticated methods are needed. Recent studies have revealed the potential of the antisymmetrized geminal power (AGP) as an excellent initial reference for the strong correlation problem. While these studies improved on AGP by linear correlators, we explore some non-linear exponential ansatze in this paper. We investigate two approaches in particular. Similar to Phys. Rev. B 91, 041114(R) (2015), we show that the similarity transformed Hamiltonian with a Hilbert-space Jastrow operator is summable to all orders and can be solved over AGP by projecting Schrodinger's equation. The second approach is based on approximating the unitary pair-hopper ansatz recently proposed for application on a quantum computer. We report benchmark numerical calculations against the ground state of the pairing Hamiltonian for both of these approaches.

References in corpus (7)

• A canonical transformation theory from extended normal ordering
• Quasiparticle Coupled Cluster Theory for Pairing Interactions
• An exactly size consistent geminal power via Jastrow factor networks in a local one particle basis
• Geminal replacement models based on AGP
• Lie Algebraic Similarity Transformed Hamiltonians for Lattice Model Systems
• Assessing the Accuracy of the Jastrow Antisymmetrized Geminal Power in the H4 Model System
• Biorthogonal projected energies of a Gutzwiller similarity transformed Hamiltonian

Cited by in corpus (2)

• Construction of linearly independent non-orthogonal AGP states
• Transition density matrices of Richardson-Gaudin states