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Defect-free model of amorphous silicon with pristine electronic structure

Louise A. M. Rosset1, Chinonso Ugwumadu2, Stephen R. Elliott3, David A. Drabold4, and Volker L. Deringer1,*

  • *Contact author: volker.deringer@chem.ox.ac.uk
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Phys. Rev. B 114, 285202 – Published 4 November, 2026

DOI: https://doi.org/10.1103/cvf3-cd4p

Abstract

Amorphous silicon (a-Si) is understood to be a canonical continuous random network material, ideally defined by fully fourfold coordination. Here, we show that a defect-free (‘‘ideal’’) model of a-Si from machine-learning-driven molecular-dynamics simulations [Rosset et al., Nat. Commun. 16, 2360 (2025)], subsequently evaluated with hybrid-level density-functional theory computations, can accurately reproduce the experimentally observed electronic band gap. We compare this model with one resulting from the Wooten-Winer-Weaire bond-switching approach and with other recent approximants to ideal a-Si. More broadly, our work provides a platform for studies of band tails, optical properties, and transport in a-Si.

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Phys. Rev. B 114, 285202– Published 4 November, 2026
  • Received 2 July 2026
  • Accepted 25 August 2026
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