We investigate the electric-pulse-induced resistance switching in manganite systems. We find a "complementarity" effect where the contact resistance of electrodes at opposite ends show variations of opposite sign and is reversible. The temperature dependence of the magnitude of the effect reveals a dramatic enhancement at a temperature T*, below the metal-insulator transition. We qualitatively capture these features with a theoretical model, providing evidence for the physical mechanism of the resistance switching. We argue that doping control of the electronic state of the oxide at the interfaces is the mechanism driving the effect.

We study the resistive switching (RS) mechanism as way to obtain multi-level memory cell (MLC) devices. In a MLC more than one bit of information can be stored in each cell. Here we identify one of the main conceptual difficulties that prevented the implementation of RS-based MLCs. We present a method to overcome these difficulties and to implement a 6-bit MLC device with a manganite-based RS device. This is done by precisely setting the remnant resistance of the RS-device to an arbitrary value. Our MLC system demonstrates that transition metal oxide non-volatile memories may compete with the currently available MLCs.

We have studied the effect of electric field on transport properties of the prototypical phase separated manganite La 5/8-y Pr y Ca 3/8 MnO 3 with y=0.34. Our results show that the suggested image in which the charge ordered state is melted by the appliance of an electric current and/or voltage has to be revised. We were able to explain the observed resistivity drop in terms of an artifact related to Joule heating and the particular hysteresis that the system under study display, common to many other phase separated manganites.

We studied La 0.325 Pr 0.300 Ca 0.375 MnO 3-Ag memristive interfaces. We present a pulsing/measuring protocol capable of registering both quasi-static i-v data and non-volatile remnant resistance. This protocol allowed distinguishing two different electronic transport mechanisms coexisting at the memristive interface, namely space charge limited current and thermionic emission limited current. We introduce a 2-element electric model that accounts for the obtained results and allows predicting the quasi-static i-v relation of the interface by means of a simple function of both the applied voltage and the remnant resistance value. Each element of the electric model is associated to one of the electronic transport mechanisms found. This electric model could result useful for developing time-domain simulation models of metal-manganite memristive interfaces. V