Molecular Dynamics Study of the Switching Mechanism of Carbon-Based Resistive Memory

An electric molecular dynamics (MD) method is proposed, where an electroheat solver is introduced into a traditional MD simulation to perform a coupled calculation. The switching mechanism of carbon-based resistive random access memory is studied through this method, and the heat generation and propagation driven by an electric current pulse are simulated during the switching process. Graphitic filament breakage and growth are responsible for resistance switching. The simulation shows that a short and strong voltage pulse induces graphitic filament breakage, resulting in a high-resistance state, whereas a moderate but much longer pulse is required to enable filament growth, resulting in a low-resistance state. Key factors such as the bias condition and the power supply for such switching process are also studied. The results are quantitatively consistent with experimental measurements.