Room‐temperature bulk plasticity and tunable dislocation densities in KTaO <sub>3</sub>
Xufei Fang, Jiawen Zhang, A. M. Frisch, Oliver Preuß, Chukwudalu Okafor, Martin Setvín, Wenjun Lu
Abstract
Abstract We report room‐temperature bulk plasticity mediated by dislocations in single‐crystal cubic potassium tantalate oxide (KTaO 3 ), contrasting the conventional knowledge that single‐crystal KTaO 3 is susceptible to brittle fracture. A mechanics‐based combinatorial experimental approach using cyclic Brinell indentation, scratching, and uniaxial bulk compression consistently demonstrates room‐temperature dislocation plasticity in KTaO 3 from the mesoscale to the macroscale. This approach also delivers tunable dislocation densities and plastic zone size. Scanning transmission electron microscopy analysis underpins the activated slip system to be <110> {10}. Given the growing significance of KTaO 3 as an emerging electronic oxide and the increasing interest in dislocations for tuning the physical properties of oxides, our findings are expected to trigger synergistic research interest in KTaO 3 with tunable dislocation densities.