Efficient $GW$ band structure calculations using Gaussian basis functions and application to atomically thin transition-metal dichalcogenides

TL;DR

This paper introduces a Gaussian basis $GW$ algorithm for periodic systems, enabling accurate and fast quasiparticle band structure calculations for atomically thin transition-metal dichalcogenides, with results comparable to traditional methods.

Contribution

The authors develop a scalable $GW$ method using Gaussian basis functions that significantly reduces computational time for 2D materials compared to plane-wave approaches.

Findings

Achieves $GW$ band gap accuracy within 50 meV of plane-wave methods.

Performs $G_0W_0$ calculations in under 30 minutes on high-performance computing resources.

Provides an efficient framework for large-scale $GW$ calculations on 2D materials.

Abstract

We present a $GW$ space-time algorithm for periodic systems in a Gaussian basis including spin-orbit coupling. We employ lattice summation to compute the irreducible density response and the self-energy, while we employ $k$-point sampling for computing the screened Coulomb interaction. Our algorithm enables accurate and computationally efficient quasiparticle band structure calculations for atomically thin transition-metal dichalcogenides. For monolayer MoS$_\text{2}$, MoSe$_\text{2}$, WS$_\text{2}$, and WSe$_\text{2}$, computed $GW$ band gaps agree on average within 50 meV with plane-wave-based reference calculations. $G_0W_0$ band structures are obtained in less than two days on a laptop (Intel i5, 192 GB RAM) or in less than 30 minutes using 1024 cores. Overall, our work provides an efficient and scalable framework for $GW$ calculations on atomically thin materials.