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arXiv · 2606.22654

Pyroelectric and electrocaloric properties of core-shell HfxZr1-xO2 nanoparticles: theory and experiment

Anna N. Morozovska·Oleksandr S. Pylypchuk·Nicholas V. Morozovsky·Eugene A. Eliseev·Dean R. Evans
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Abstract

Nanosized hafnia-zirconia (HfxZr1-xO2) in the form of thin films, multilayers, and nanoparticles is one of the most promising CMOS-compatible ferroelectric materials for advanced electronic memories and logic devices. Using the Landau-Ginzburg-Devonshire free energy functional with trilinear and biquadratic couplings of polar, nonpolar, and antipolar order parameters, we analyze the pyroelectric and electrocaloric properties in an ensemble of spherical core-shell HfxZr1-xO2 nanoparticles. To test the theoretical model, we experimentally measured the temperature dependence of the electric charge accumulated in pressed powders consisting of oxygen-deficient core-shell Hf0.5Zr0.5O2 nanoparticles with an average size of 7 nm. The observed temperature-dependent behavior of the accumulated charge and its derivative are in qualitative agreement with the calculated polarization and pyroelectric coefficient for the ensemble of densely packed spherical core-shell HfxZr1-xO2 nanoparticles; this suggests that the theoretical model captures the physical mechanisms responsible for the experimentally observed charge accumulation. The combined theoretical and experimental results provide a physical foundation for the future development of CMOS-compatible HfxZr1-xO2 nanoparticles for pyroelectric and electrocaloric applications.

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BibTeXRIS

Anna N. Morozovska, Oleksandr S. Pylypchuk, Nicholas V. Morozovsky, Eugene A. Eliseev, Dean R. Evans. 2026-06-21. Pyroelectric and electrocaloric properties of core-shell HfxZr1-xO2 nanoparticles: theory and experiment. https://arxiv.org/abs/2606.22654

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