Dislocation tuned flexoelectricity in single crystal SrTiO₃

Flexoelectricity, an intrinsic electromechanical coupling phenomenon, has shown great potential in advanced ceramic. However, the typically low flexoelectric coefficients of bulk materials severely limit their practical applications, especially for single crystals. Surprisingly, recent advances have demonstrated that room-temperature dislocation engineering can effectively modulate functional properties. In this study, we employ the cyclic indentation method to introduce controlled surface dislocations into single-crystal SrTiO₃ with (100), (110), and (111) orientations. Precise regulation of indentation cycles enables tunable flexoelectric coefficients with pronounced orientation dependence. Comprehensive characterization reveals a direct correlation between surface dislocation configurations and bulk flexoelectric response. These results demonstrate an effective and controllable strategy for the controlled modulation of flexoelectric properties in single crystals, providing a foundation for further development of high-performance flexoelectric-based novel electromechanical devices.