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arXiv · 2408.01830

Antiferroelectric Hafnia Down to the 2D Limit

Xin Li·Guodong Ren·Haidong Lu·Kartik Samanta·Amit Kumar Shah·Kai Huang·Pravan Omprakash·Yu Yun·Pratyush Buragohain·Huibo Cao·Yan Wu·Jordan A. Hachtel·Andrew R. Lupini·Miaofang Chi·Juan Carlos Idrobo·Evgeny Y. Tsymbal·Alexei Gruverman·Rohan Mishra·Xiaoshan Xu
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Abstract

Antiferroelectricity is a material property characterized by alternating electric dipoles spontaneously ordered in antiparallel directions. Antiferroelectrics are promising for energy storage, solid-state cooling, and memory technologies; however, these materials are scarce, and their scalability remains largely unexplored. In this work, we demonstrate that single-crystalline hafnia, a lead-free CMOS-compatible material, exhibits antiferroelectricity under compressive-strain conditions. We observe antiparallel sublattice polarization and stable double-hysteresis in single-crystalline (111)-oriented epitaxial La-doped hafnia films grown on yttrium-stabilized zirconia and show that the antipolar orthorhombic phase of hafnia adheres to the Kittel model of antiferroelectricity. Notably, compressive strain strengthens the antiferroelectric order in thinner La-doped hafnia films, achieving an unprecedented 850 C ordering temperature in the two-dimensional limit, highlighting hafnia's potential for advanced antiferroelectric devices.

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Xin Li, Guodong Ren, Haidong Lu, Kartik Samanta, Amit Kumar Shah, Kai Huang, Pravan Omprakash, Yu Yun, Pratyush Buragohain, Huibo Cao, Yan Wu, Jordan A. Hachtel, Andrew R. Lupini, Miaofang Chi, Juan Carlos Idrobo, Evgeny Y. Tsymbal, Alexei Gruverman, Rohan Mishra, Xiaoshan Xu. 2025-08-02. Antiferroelectric Hafnia Down to the 2D Limit. https://arxiv.org/abs/2408.01830

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