{"ID":2878176,"CreatedAt":"2026-06-01T04:54:23.091178241Z","UpdatedAt":"2026-06-01T04:54:23.091178241Z","DeletedAt":null,"paper_url":"https://arxiv.org/abs/2508.19138","arxiv_id":"2508.19138","title":"Ab-initio Quantum Transport with the GW Approximation, 42,240 Atoms, and Sustained Exascale Performance","abstract":"Designing nanoscale electronic devices such as the currently manufactured nanoribbon field-effect transistors (NRFETs) requires advanced modeling tools capturing all relevant quantum mechanical effects. State-of-the-art approaches combine the non-equilibrium Green's function (NEGF) formalism and density functional theory (DFT). However, as device dimensions do not exceed a few nanometers anymore, electrons are confined in ultra-small volumes, giving rise to strong electron-electron interactions. To account for these critical effects, DFT+NEGF solvers should be extended with the GW approximation, which massively increases their computational intensity. Here, we present the first implementation of the NEGF+GW scheme capable of handling NRFET geometries with dimensions comparable to experiments. This package, called QuaTrEx, makes use of a novel spatial domain decomposition scheme, can treat devices made of up to 84,480 atoms, scales very well on the Alps and Frontier supercomputers (\u003e80% weak scaling efficiency), and sustains an exascale FP64 performance on 42,240 atoms (1.15 Eflop/s).","short_abstract":"Designing nanoscale electronic devices such as the currently manufactured nanoribbon field-effect transistors (NRFETs) requires advanced modeling tools capturing all relevant quantum mechanical effects. State-of-the-art approaches combine the non-equilibrium Green's function (NEGF) formalism and density functional theo...","url_abs":"https://arxiv.org/abs/2508.19138","url_pdf":"https://arxiv.org/pdf/2508.19138v1","authors":"[\"Nicolas Vetsch\",\"Alexander Maeder\",\"Vincent Maillou\",\"Anders Winka\",\"Jiang Cao\",\"Grzegorz Kwasniewski\",\"Leonard Deuschle\",\"Torsten Hoefler\",\"Alexandros Nikolaos Ziogas\",\"Mathieu Luisier\"]","published":"2025-08-26T15:42:45Z","proceeding":"cs.DC","tasks":"[\"cs.DC\",\"cond-mat.mes-hall\",\"cs.CE\"]","methods":"[]","has_code":false}