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arXiv · 2608.26678

A solid-solution approach for room-temperature bulk plasticity in KTa1-xNbxO3

Alexander Frisch·Jiawen Zhang·Martin Setvin·Xuping Wang·Wenjun Lu·Xufei Fang
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Abstract

Dislocations are being engineered into perovskite oxides to harvest versatile functional properties. One major bottleneck, however, persists: perovskite oxides that can be engineered with dislocations, particularly via mechanical deformation at room temperature in bulk scale, have so far been limited to only three materials: SrTiO3 (2001, Brunner et al.), KNbO3 (2016, Mark et al.), and KTaO3 (2024, Fang & Zhang et al.). Here, we propose a simple and effective approach by using solid solution to significantly extend the range of materials. We showcase KTa1-xNbxO3 (0<x<1) perovskite oxides for their bulk plasticity at room temperature by constructing a closed-loop validation workflow that includes crystal growth, Brinell indentation, bulk compression, and transmission electron microscopy characterization. Our findings are expected to unlock the materials toolbox for dislocation-tuned functionality of perovskite oxides.

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Alexander Frisch, Jiawen Zhang, Martin Setvin, Xuping Wang, Wenjun Lu, Xufei Fang. 2026-08-27. A solid-solution approach for room-temperature bulk plasticity in KTa1-xNbxO3. https://arxiv.org/abs/2608.26678

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