On Bidirectional Transition Between Threshold and Bipolar Switching in Ag/SiO$_{2}$/ITO Memristors

An Ag/SiO$_{2}$/ITO thin-film memristor with a simple deposition technique that exhibits bidirectional threshold and bipolar memristive switching is presented. By applying adequate compliance currents, the switching mechanism of the memristor can be transitioned from threshold switching to bipolar switching. The reverse transition, from bipolar to threshold can be realized by applying a large negative current. This bidirectional switching is stable and reproducible, which has been proven by multiple experimental results. In addition, Verilog-A based modeling approach of this directional switching mechanism is also presented.