Mixed Stochastic-Deterministic Approach for Many-Body Perturbation Theory Calculations

Aaron R. Altman, Sudipta Kundu, and Felipe H. da Jornada

Phys. Rev. Lett. 132, 086401 – Published 20 February 2024

Abstract

We present an approach for $G W$ calculations of quasiparticle energies with quasiquadratic scaling by approximating high-energy contributions to the Green’s function in its Lehmann representation with effective stochastic vectors. The method is easy to implement without altering the $G W$ code, converges rapidly with stochastic parameters, and treats systems of various dimensionality and screening response. Our calculations on a 5.75° twisted ${MoS}_{2}$ bilayer show how large-scale $G W$ methods include geometry relaxations and electronic correlations on an equal basis in structurally nontrivial materials.

Received 7 April 2023
Revised 24 August 2023
Accepted 5 December 2023

DOI:https://doi.org/10.1103/PhysRevLett.132.086401

Physics Subject Headings (PhySH)

Electronic structure First-principles calculations Quasiparticles & collective excitations

Molecules Semiconductor compounds

Approximation methods for many-body systems Electron-correlation calculations GW method

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

Aaron R. Altman ¹, Sudipta Kundu ¹, and Felipe H. da Jornada ^1,2,*

¹Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, USA
²Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA