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arXiv · 2412.21105

Heterostructure Engineering for Wurtzite LaN

Andrew J. E. Rowberg·Sai Mu·Chris G. Van de Walle
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Abstract

Wurtzite LaN (wz-LaN) is a semiconducting nitride with favorable piezoelectric and ferroelectric properties, making it promising for applications in electronics. We use first-principles density functional theory with a hybrid functional to investigate several features that are key for its use in heterostructures. First, for the purposes of growing wz-LaN on a substrate or designing a heterostructure, we show that it can be lattice-matched with a number of cubic materials along their [111] axes. We also evaluate the bound charge at such interfaces, taking into account both the polarization discontinuity and the piezoelectric polarization due to pseudomorphic strain. Second, we investigate band alignments and assess the results for interfaces with zincblende-, rocksalt-, and perovskite-structure compounds, and with chemically similar wurtzite and rocksalt nitrides. Our results provide guidance for the development of electronic devices based on wz-LaN.

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Andrew J. E. Rowberg, Sai Mu, Chris G. Van de Walle. 2024-12-30. Heterostructure Engineering for Wurtzite LaN. https://doi.org/10.1063/5.0255815

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