Periodic Coupled-Cluster Green's Function for Photoemission Spectra of Realistic Solids

TL;DR

This paper introduces an efficient periodic coupled-cluster Green's function method with active-space self-energy correction and model order reduction, enabling accurate photoemission spectra simulations of realistic solids like Si and ZnO.

Contribution

It develops a novel periodic CCGF approach with cost-reducing techniques, allowing practical high-accuracy simulations of complex solids.

Findings

Accurate spectral properties of Si and ZnO match experimental data.

Active-space self-energy correction improves computational efficiency.

MOR frequency interpolation maintains high accuracy with reduced cost.

Abstract

We present an efficient implementation of coupled-cluster Green's function (CCGF) method for simulating photoemission spectra of periodic systems. We formulate the periodic CCGF approach with Brillouin zone sampling in Gaussian basis at the coupled-cluster singles and doubles (CCSD) level. To enable CCGF calculations of realistic solids, we propose an active-space self-energy correction scheme by combining CCGF with cheaper many-body perturbation theory (GW) and implement the model order reduction (MOR) frequency interpolation technique. We find that the active-space self-energy correction and MOR techniques significantly reduce the computational cost of CCGF while maintaining the high accuracy. We apply the developed CCGF approaches to compute spectral properties and band structure of silicon (Si) and zinc oxide (ZnO) crystals using triple-$\zeta$ Gaussian basis and medium-size k-point sampling, and find good agreement with experimental measurements.