  Ab initio calculation of dielectric response with high-accuracy electronic
structure methods is a long-standing problem, for which mean-field approaches
are widely used and electron correlations are mostly treated via approximated
functionals. Here we employ a neural network wavefunction ansatz combined with
quantum Monte Carlo to incorporate correlations into polarization calculations.
On a variety of systems, including isolated atoms, one-dimensional chains,
two-dimensional slabs, and three-dimensional cubes, the calculated results
outperform conventional density functional theory and are consistent with the
most accurate calculations and experimental data. Furthermore, we have studied
the out-of-plane dielectric constant of bilayer graphene using our method and
re-established its thickness dependence. Overall, this approach provides a
powerful tool to consider electron correlation in the modern theory of
polarization.
