We report on non-volatile memory devices based on multifunctional manganites.The electric field induced resistive switching ofTi/$La_{1/3}$$Ca_{2/3}$Mn$O_3$/n-Si devices is explored using differentmeasurement protocols. We show that using current as the electrical stimulus(instead of standard voltage-controlled protocols) improves the electricalperformance of our devices and unveils an intermediate resistance state. Weobserve three discrete resistance levels (low, intermediate and high), whichcan be set either by the application of current-voltage ramps or by means ofsingle pulses. These states exhibit retention and endurance capabilitiesexceeding $10^4$ s and 70 cycles, respectively. We rationalize our experimentalobservations by proposing a mixed scenario were a metallic filament and aSi$O_x$ layer coexist, accounting for the observed resistive switching. Overallelectrode area dependence and temperature dependent resistance measurementssupport our scenario. After device failure takes place, the system can beturned functional again by heating up to low temperature (120 C), a featurethat could be exploited for the design of memristive devices with self-healingfunctionality. These results give insight into the existence of multipleresistive switching mechanisms in manganite-based memristive systems andprovide strategies for controlling them.
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