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arXiv · 2510.04783

Electronic and thermal properties of the phase-change memory material, Ge2Sb2Te5, and results from spatially resolved transport calculations

Kishor Nepal·Aashish Gautam·Ridwan Hussein·Konstantinos Konstantinou·Stephen. R. Elliott·Chinonso Ugwumadu·David A. Drabold
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Abstract

We report new insights into the electronic, structural, and transport (heat and charge) properties of the phase-change memory material Ge2Sb2Te5. Using realistic structural models of Konstantinou et. al. [Nat. Commun. 10, 3065 (2019)], we analyze the topology, electronic states, and lattice dynamics with density functional methods, including hybrid-functional calculations and machine-learned interatomic potentials. The Kohn-Sham orbitals near the Fermi level display a strong electron-phonon coupling, and exhibit large energy fluctuations at room temperature. The conduction tail states exhibit larger phonon-induced fluctuations than the valence tail states. To resolve transport at the atomic scale, we employ space-projected electronic conductivity and site-projected thermal conductivity methods. Local analysis of heat transport highlights the role of filamentary networks dominated by Te, with Sb and Ge making progressively smaller contributions.

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Kishor Nepal, Aashish Gautam, Ridwan Hussein, Konstantinos Konstantinou, Stephen. R. Elliott, Chinonso Ugwumadu, David A. Drabold. 2025-10-06. Electronic and thermal properties of the phase-change memory material, Ge2Sb2Te5, and results from spatially resolved transport calculations. https://arxiv.org/abs/2510.04783

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