Spatiotemporal Ferro-Ionic Dynamics in Van der Waals Ferroelectrics

Van der Waals CuInP2S6 represents a model ferro–ionic system where copper ion migration controls the polarization states and current evolution, having exciting applications in neuromorphic computing and memristive devices. However, a fundamental challenge still remains in resolving the long-standing uncertainty about the origin of dynamic currents in ferroionic system. Herein, based on a pulsed tip-based methodology, the present work accomplishes efficient manipulation of nanoscale ferro-ionic dynamics and disentangles the individual contribution from ferroelectric switching to dynamic currents. Moreover, this work further reveals the origin of multiple current peaks and establishes a mechanism of spatiotemporal ferro-ionic dynamics. This mechanistic insight goes beyond previous studies that focused solely on temporal or electric‑field dependence, which is an important step toward high‑performance ferroionic memristors.