pyqsci

pyqsci is an unofficial Quantum Selected CI library in PySCF and PennyLane

Features

• Selected CI for quantum computing
  • see https://arxiv.org/abs/2302.11320

Usages

from qsci import qsciclass, vqe
import numpy as np
norb = 2
nelec = 2
int1e = np.random.rand(norb, norb)
int1e = int1e + int1e.T
int2e = np.zeros((norb, norb, norb, norb))
uccsd = vqe.UCCSD_Lattice(int1e, int2e, norb, nelec)
uccsd.optimize()
smp = qsciclass.Sampler(uccsd)
qscicls = qsciclass.QSCI(smp)
e, c, _ = qscicls.diagonalize_sci()
print(e)
print(c)

from pyscf import fci

cis = fci.direct_spin1.FCISolver()
e, c = cis.kernel(int1e, int2e, norb, nelec)
print(e)
print(c)

Installation

conda create -n qsci_exp python=3.9
conda activate qsci_exp
git clone https://github.com/nkitamuraQC/qsci_exp.git
cd qsci_exp
pip install -e .