Power signatures of electric field and thermal switching regimes in memristive SET transitions

We present a study of the 'snap-back' regime of resistive switching hysteresis in bipolar TaO_x memristors, identifying power signatures in the electronic transport. Using a simple model based on the thermal and electric field acceleration of ionic mobilities, we provide evidence that the 'snap-back' transition represents a crossover from a coupled thermal and electric-field regime to a primarily thermal regime, and is dictated by the reconnection of a ruptured conducting filament. We discuss how these power signatures can be used to limit filament radius growth, which is important for operational properties such as power, speed, and retention. (paper)