OpenVQE: README

OpenVQE is an Open Source Variational Quantum Eigensolver extension of the Quantum Learning Machine to Quantum Chemistry. It was developed based on the tools of myqlm-fermion

Check the main OpenVQE paper: Open Source Variational Quantum Eigensolver Extension of the Quantum Learning Machine (QLM) for Quantum Chemistry. M. Haidar, M. J. Rančić, T. Ayral, Y. Maday, J.-P. Piquemal, WIREs Comp. Mol. Sci., 2023, e1664 (Open Access) DOI: 10.1002/wcms.1664

It consists of two main modules as follows:

• UCC Family: this module consists of different classes and functions to generate the fermionic cluster operators (fermionic pool) and the qubit pools and to get the optimized energies from VQE in the case of active and non-active orbital selections. For example, UCCSD, QUCCSD, UCCGSD, K-UpCCGSD, spin-complemented pair, singlet and doublet generalized single and double excitations, etc.

• ADAPT: consists of two sub-modules which are:

  • Fermionic-ADAPT: it contains functions that performs the fermionic ADAPT-VQE algorthmic steps in the active and non-active space selections.
  • Qubit-ADAPT: it contains functions that perform the Qubit ADAPT-VQE algorithmic steps calculation in the active and non-active space orbital selections.

Installation

Prerequisites:

Install myqlm-fermion:

install myqlm-fermion 1.7.1 from source:

git clone https://github.com/myQLM/myqlm-fermion.git
cd myqlm-fermion
git checkout 1.7.1
pip install -r requirements.txt
pip install .

Install OpenVQE

install OpenVQE from source:

git clone https://github.com/OpenVQE/OpenVQE.git
cd OpenVQE
pip install -r requirements.txt
pip install .

Move to the next section for getting started!

Getting started

Notebooks

Jupyter notebooks are available in the "notebooks" folder.

Hello world example

from openvqe.ucc import ...

Documentation

The code is based on the well documented code of myqlm-fermion framework link. The main functions are documented in the code base. For more information, please refer to our paper that wil be published soon (the link to be provided).

How to cite

Mohammad Haidar, Marko J. Ranˇci´c, Thomas Ayral, Yvon Maday, and Jean-Philip Piquemal. Open source variational quantum eigensolver extension of the quantum learning machine for quantum chemistry. WIREs Computational Molecular Science, page e1664, 2023

Getting in touch

For any question about OpenVQE or my research, don't hesitate to get in touch: [email protected]

License

OpenVQE was created by Mohammad Haidar. It is licensed under the terms of the MIT License.

References

• Nooijen, Marcel. "Can the eigenstates of a many-body hamiltonian be represented exactly using a general two-body cluster expansion?." Physical review letters 84.10 (2000): 2108.
• Lee, Joonho, et al. "Generalized unitary coupled cluster wave functions for quantum computation." Journal of chemical theory and computation 15.1 (2018): 311-324.
• Grimsley, Harper R., et al. "An adaptive variational algorithm for exact molecular simulations on a quantum computer." Nature communications 10.1 (2019): 1-9.
• Tang, Ho Lun, et al. "qubit-adapt-vqe: An adaptive algorithm for constructing hardware-efficient ansätze on a quantum processor." PRX Quantum 2.2 (2021): 020310.
• Xia, Rongxin, and Sabre Kais. "Qubit coupled cluster singles and doubles variational quantum eigensolver ansatz for electronic structure calculations." Quantum Science and Technology 6.1 (2020): 015001.
• Shkolnikov, V. O., et al. "Avoiding symmetry roadblocks and minimizing the measurement overhead of adaptive variational quantum eigensolvers." arXiv preprint arXiv:2109.05340 (2021).