Reversible writing of high-density dislocations with multidimensional controllability in PMN-PT crystal

Controllable dislocations are highly desirable for modulating the physicochemical properties of materials and innovating scientific research and engineering applications. Therefore, technologies that can flexibly manipulate dislocations with high precision have long been sought. Recently, non-mechanical approaches have shown great potential in dislocation manipulation but are mostly restricted to the limited control degrees of freedom. Here, we present a method for reversible writing of high-density dislocations (~10¹⁶m^-2) in Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃ (PMN-PT) single crystals by ultrafast laser-driven energy deposition. The dislocations exhibit a multi-dimensionally controllable spatial distribution and can be repeatedly written and erased in 3D space. We reveal that the ultrafast laser-matter interaction-induced anisotropic field enhancement cooperates with the orientation of ferroelectric domains to dominate the dislocation manipulation, and the annihilation behavior of high-density dislocations is the nature of their erasable characteristics. This study provides an effective approach for multi-degree-of-freedom dislocation control by non-mechanical stimuli and opens up new possibilities for dislocation-mediated innovative applications.