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arXiv · 2606.20500

A Defect-Free Model of Amorphous Silicon with Pristine Electronic Structure

Louise A. M. Rosset·Chinonso Ugwumadu·Stephen R. Elliott·David A. Drabold·Volker L. Deringer
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Abstract

Amorphous silicon (a-Si) is understood to be the 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 [L. A. M. Rosset et al., Nat. Commun. 16, 2360 (2025)], subsequently evaluated with hybrid-level density-functional theory computations, can accurately reproduce the experimentally observed electronic bandgap. We compare this model with one resulting from the Wooten-Winer-Weaire (WWW) 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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Louise A. M. Rosset, Chinonso Ugwumadu, Stephen R. Elliott, David A. Drabold, Volker L. Deringer. 2026-06-18. A Defect-Free Model of Amorphous Silicon with Pristine Electronic Structure. https://arxiv.org/abs/2606.20500

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