Unitary coupled-cluster based self-consistent polarization propagator theory: a quadratic unitary coupled-cluster singles and doubles scheme

Abstract

The development of a quadratic unitary coupled-cluster singles and doubles (qUCCSD) based self-consistent polarization propagator method is reported. We present a simple strategy for truncating the commutator expansion of the UCC transformed Hamiltonian $\bar{H}$. The qUCCSD method for the electronic ground-state includes up to double commutators for the amplitude equations and up to cubic commutators for the energy expression. The qUCCSD excited-state eigenvalue equations include up to double commutators for the singles-singles block of $\bar{H}$, single commutators for the singles-doubles and doubles-singles blocks, and the bare Hamiltonian for the doubles-doubles block. Benchmark qUCCSD calculations of the ground-state properties and excitation energies for representative molecules demonstrate significant improvement of the accuracy and robustness over the previous UCC3 scheme derived using Møller-Plesset perturbation theory.

References in corpus (18)

• A variational eigenvalue solver on a quantum processor
• An adaptive variational algorithm for exact molecular simulations on a quantum computer
• Towards Practical Quantum Variational Algorithms
• Generalized Unitary Coupled Cluster Wavefunctions for Quantum Computation
• Quantum algorithms for electronic structure calculations: particle/hole Hamiltonian and optimized wavefunction expansions
• Exact Parameterization of Fermionic Wave Functions via Unitary Coupled Cluster Theory
• Quantum Orbital-Optimized Unitary Coupled Cluster Methods in the Strongly Correlated Regime: Can Quantum Algorithms Outperform their Classical Equivalents?
• On the difference between variational and unitary coupled cluster theories
• On The Relation Between Equation-of-Motion Coupled-Cluster Theory and the GW Approximation
• Spectral Functions of the Uniform Electron Gas via Coupled-Cluster Theory and Comparison to the $GW$ and Related Approximations
• Crossing conditions in coupled cluster theory
• Third-order algebraic diagrammatic construction theory for electron attachment and ionization energies: Conventional and Green's function implementation
• A periodic equation-of-motion coupled-cluster implementation applied to $F$-centers in alkaline earth oxides
• Complex Ground-State and Excitation Energies in Coupled-Cluster Theory
• A Stochastic Approach to Unitary Coupled Cluster
• Efficient implementation of the single-reference algebraic diagrammatic construction theory for charged excitations: Applications to the TEMPO radical and DNA base pairs
• First principles coupled cluster theory of the electronic spectrum of the transition metal dichalcogenides
• Assessing the Orbital-Optimized Unitary Ansatz for Density Cumulant Theory

Cited by in corpus (4)

• Simulating the electronic structure of spin defects on quantum computers
• Quantum simulations of Fermionic Hamiltonians with efficient encoding and ansatz schemes
• A new "gold standard": perturbative triples corrections in unitary coupled cluster theory and prospects for quantum computing
• Equation-of-motion internally contracted multireference unitary coupled-cluster theory