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arXiv · 2102.13296

Ultrahigh energy storage density in epitaxial AlN/ScN superlattices

Zhijun Jiang·Bin Xu·Hongjun Xiang·L. Bellaiche
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Abstract

Dielectric and antiferroelectric materials are particularly promising for high-power energy-storage applications. However, relatively low energy density greatly hinders their usage in storage technologies. Here, we report first-principles-based calculations predicting that epitaxial and initially non-polar AlN/ScN superlattices can achieve an ultrahigh energy density of up to 200 J/cm$^{\textrm{3}}$, accompanied by an ideal efficiency of 100%. We also show that high energy density requires the system being neither too close nor too far from a ferroelectric phase transition under zero electric field. A phenomenological model is further proposed to rationalize such striking features.

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Zhijun Jiang, Bin Xu, Hongjun Xiang, L. Bellaiche. 2021-02-26. Ultrahigh energy storage density in epitaxial AlN/ScN superlattices. https://doi.org/10.1103/physrevmaterials.5.l072401

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