Room‐temperature bulk plasticity and tunable dislocation densities in KTaO₃

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.