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arXiv · 2502.11754

New insights into crystallographic relation and lattice dynamics effects in {CdO/MgO} superlattices grown by plasma-assisted molecular beam epitaxy

Aleksandra Wierzbicka·Ewa Przezdziecka·Igor Perlikowski·Eunika Zielony·Abinash Adhikari·Anastasiia Lysak
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Abstract

This article explores the structural properties of molecular beam epitaxy grown {CdO/MgO} superlattices on sapphire substrates of different crystallographic orientations (a-, c-, r-, and m-plane). The investigations involve a comprehensive analysis using X-ray diffraction and Raman spectroscopy. High-resolution X-ray diffraction studies unveil a significant influence of surface symmetry on both the substrates and the epitaxial layers, particularly with respect to the occurrence of twins in the superlattices. Remarkably, no twins are observed on r-oriented sapphire substrates, resulting in improved interface and crystallographic quality. The results of studies demonstrated in this work show that the growth rate of CdO sublayers within {CdO/MgO} superlattices is intricately dependent on the substrate orientation. Notably, the c-plane and m-plane sapphire substrates yielded thicker CdO sublayers, indicating comparable growth rates for these crystallographic orientations. Conversely, the a-plane and r-plane orientations seemed to favor a slower growth rate of CdO sublayers.

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Aleksandra Wierzbicka, Ewa Przezdziecka, Igor Perlikowski, Eunika Zielony, Abinash Adhikari, Anastasiia Lysak. 2025-02-17. New insights into crystallographic relation and lattice dynamics effects in {CdO/MgO} superlattices grown by plasma-assisted molecular beam epitaxy. https://arxiv.org/abs/2502.11754

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