Exploring Parameter Redundancy in the Unitary Coupled-Cluster Ansatze for Hybrid Variational Quantum Computing
arXiv:2301.09825 · doi:10.1021/acs.jpca.3c00550
Abstract
One of the commonly used chemical-inspired approaches in variational quantum computing is the unitary coupled-cluster (UCC) ansatze. Despite being a systematic way of approaching the exact limit, the number of parameters in the standard UCC ansatze exhibits unfavorable scaling with respect to the system size, hindering its practical use on near-term quantum devices. Efforts have been taken to propose some variants of UCC ansatze with better scaling. In this paper we explore the parameter redundancy in the preparation of unitary coupled-cluster singles and doubles (UCCSD) ansatze employing spin-adapted formulation, small amplitude filtration, and entropy-based orbital selection approaches. Numerical results of using our approach on some small molecules have exhibited a significant cost reduction in the number of parameters to be optimized and in the time to convergence compared with conventional UCCSD-VQE simulations. We also discuss the potential application of some machine learning techniques in further exploring the parameter redundancy, providing a possible direction for future studies.
References in corpus (32)
- SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
- A variational eigenvalue solver on a quantum processor
- Recurrence Plots for the Analysis of Complex Systems
- Hardware-efficient Variational Quantum Eigensolver for Small Molecules and Quantum Magnets
- Barren plateaus in quantum neural network training landscapes
- The Variational Quantum Eigensolver: a review of methods and best practices
- An adaptive variational algorithm for exact molecular simulations on a quantum computer
- Extending the computational reach of a noisy superconducting quantum processor
- Generalized Unitary Coupled Cluster Wavefunctions for Quantum Computation
- Quantum Simulation of Electronic Structure with Linear Depth and Connectivity
- Measuring orbital interaction using quantum information theory
- A Quantum Computing View on Unitary Coupled Cluster Theory
- Exact Parameterization of Fermionic Wave Functions via Unitary Coupled Cluster Theory
- Quantum circuits for strongly correlated quantum systems
- Orbital entanglement in bond-formation processes
- Qubit-excitation-based adaptive variational quantum eigensolver
- Orbital optimized unitary coupled cluster theory for quantum computer
- Entanglement as Measure of Electron-Electron Correlation in Quantum Chemistry Calculations
- Orbital entanglement in quantum chemistry
- Efficient quantum circuits for quantum computational chemistry
- Downfolding of many-body Hamiltonians using active-space models: extension of the sub-system embedding sub-algebras approach to unitary coupled cluster formalisms
- Accuracy and Resource Estimations for Quantum Chemistry on a Near-term Quantum Computer
- Variational Quantum Eigensolver with Reduced Circuit Complexity
- Mutual information-assisted Adaptive Variational Quantum Eigensolver
- Spin-projection for quantum computation: A low-depth approach to strong correlation
- Sub-system quantum dynamics using coupled cluster downfolding techniques
- Unitary Selective Coupled-Cluster Method
- Classical and Quantum Algorithms for Orthogonal Neural Networks
- Accelerating Coupled Cluster Calculations with Nonlinear Dynamics and Shallow Machine Learning
- An Approximate Coupled Cluster Theory via Nonlinear Dynamics and Synergetics: the Adiabatic Decoupling Conditions
- Large-scale sparse wavefunction circuit simulator for applications with the variational quantum eigensolver
- Leveraging small scale quantum computers with unitarily downfolded Hamiltonians