Resistive switching polarity reversal due to ferroelectrically induced phase transition at BiFeO₃/Ca_0.96Ce_0.04MnO₃heterostructures

Ferroelectric resistive switching (RS) devices with functional oxide electrodes allow controlled emergent phenomena at an interface. Here, we demonstrate RS polarity reversal due to ferroelectrically induced phase transition at a doped charge transfer insulator interface. For BiFeO3/Ca0.96Ce0.04MnO3 bilayers grown on a NdAlO3 substrate, by applying voltages to a Ca0.96Ce0.04MnO3 bottom electrode, the resistance changes from a high resistance state (HRS) to a low resistance state (LRS) during a positive voltage cycle (0 → 3 → 0 V), and from a LRS to a HRS during a negative voltage cycle (0 → -3 → 0 V). The RS polarity is completely opposite the expected RS behavior in ferroelectric heterostructures induced by polarization reversal. It is proposed that the unique resistance switching polarity is attributed to the band-filling controlled metal-insulator transition in a Ca0.96Ce0.04MnO3 film, triggered by ferroelectric based electrostatic doping. The results address the importance of ferroelectric field effect on the electronic properties of the interfacial system in ferroelectric/complex oxide-based resistive memory devices.