Quantum Eigensolver Building on Achievments of Both quantum computing and chemistry (QEBAB)

Tools for building quantum chemistry Variational Quantum Eigensolver (VQE) calculations.

Setup

1. (Recommended) Create a new conda environment

$ conda create -n qebab python
$ conda activate qebab

2. Clone repo

$ mkdir QEBAB
$ cd QEBAB
$ git clone https://github.com/hanschanhs/QEBAB.git

3. Install required packages

Availabe tools

Operator pool types

• Unitary Coupled Cluster Singles and Doubles (UCCSD)
• Unitary Coupled Cluster Generalised Singles and Doubles (UCCGSD)
• Unitary Coupled Cluster Generalised Singles and paired Doubles (UpCCGSD)

Ansatz build classes

• k-UCC type: string up operators from a pool, and repeat k times, each time with a separate parameterisation. For conventional (disentangled) 1-Trotter UCCSD/UCCGSD, set k=1.
• ADAPT type: adaptive ansatz growth

Reference circuits

• singlet (Hartree-Fock) reference
• triplet (first excited) reference

Build examples use Variational Quantum Deflation (VQD). For ground state VQE calculations, set the number of eigenstates recovered to 1.