Investigation of Plasticity in Memristive Structures Based on Nd2 – xCexCuO4 – y Epitaxial Films

Pulse investigations of resistive switching in planar memristive heterocontacts based on Nd_2 – xC-e_xCuO_4 – y epitaxial films are presented. The possibility of regulating metastable resistive states in planar memristive systems based on such films is studied using specific protocols of pulse measurements. Various metastable states are implemented by changing external parameters: the frequency and magnitude of the electric-field voltage applied to the heterocontacts. Dynamic effects are investigated, and the transition times between metastable states are determined. Direct investigation involves alteration of the electrodynamic properties under the effect of a sinusoidal alternating electric field at frequencies of 10^–3 Hz and in the pulsed mode with pulse durations ranging from 0.1 ms to 25 s. This is accomplished by measuring the current–voltage characteristics, recording the current and voltage oscillograms at the heterocontact, and examining the temperature-dependent resistivity of metastable phases. The multilevel nature of the metastable resistive states in the studied systems and the ability to control switching times characterize the adaptability of these devices and their potential use as memory elements for neuromorphic applications in spiking neural networks.