A memristive n-p diode with giant memcapacitance

ACEVEDO, W ROMÁN; VAN DEN BOSCH, C. A. M.; AGUIRRE, M; ACHA, C; A. CAVALLARO; C. FERREYRA; SÁNCHEZ, M.J.; L. PATRONE; A. AGUADERO; D RUBI

Dresden

Conferencia; MEMRISYS; 2019

Memristive devices with added functionalities such as robust memcapacitance could outperformstandard memristors in key aspects such as power consumption or miniaturization possibilities.Here we demonstrate a giant memcapacitive response of a perovskite memristive interface, usingthe topotactic redox ability of La0.5Sr0.5Mn0.5Co0.5O3-δ (LSMCO, 0 ≤ δ ≤ 0.62). OurNb:SrTiO3/LSMCO/Pt devices require an initial electroformimg process where extended nanochannelsfor easy oxygen diffusion in and out of the device are created, as verified by highresolution transmission electron microscopy. From extensive electrical characterization andmodeling, we determined that the observed multi-mem behavior originates at the switchable n-pdiode formed at the Nb:SrTiO3/LSMCO interface. We found a memcapacitive effect CHIGH/CLOW ~104 for the n-p interface and > 300 for the complete device, which is the largest figure measured todate by a factor of 30. Our work paves the way for the implementation of topotactic redox materialsin novel neuromorphic computing devices.