Manipulation of Topological Antiskyrmion Lattice Transition at Room Temperature

Skyrmion systems have been regarded as potential candidates for versatile energy-efficient information processing due to the intrinsic topological properties. In emerging skyrmion-based reservoir computing concepts, history-dependent spin state evolution constitutes a key physical ingredient, highlighting the importance of controllable collective dynamics in response to external stimuli. Antiskyrmions, as antiparticles of skyrmions, are expected to offer additional configurational degrees of freedom and enhanced thermal stability. However, experimental visualization of their field-dependent collective evolution remains scarce. Here we report a continuous, field-history-dependent antiskyrmion transition from a triangular to square lattice, accompanied by a sequence of intricate intermediate states in Mn_1.4PtSn chiral magnet. Coordinated variations in antiskyrmion shape, size, and position are directly demonstrated, thereby offering experimentally multiple accessible degrees of freedom under controlled magnetic-field inputs. Systematic micromagnetic simulations reveal that the competition among Dzyaloshinskii–Moriya, dipolar, and Zeeman interactions governs the sequential reconfiguration of local spin textures underlying the observed lattice evolution. Our results provide a controllable and history-dependent antiskyrmion lattice platform with rich intermediate configuration states to explore multi-level information encoding and reservoir-computing applications.