Noise Tailoring in Memristive Filaments
Botond Sánta, Zoltán Balogh, László Pósa, Dávid Krisztián, Tímea Nóra Török, Dániel Molnár, Csaba Sinkó, Roland Hauert, Miklós Csontos, András Halbritter
Abstract
In this study, the possibilities of noise tailoring in filamentary resistive switching memory devices are investigated. To this end, the resistance and frequency scaling of the lowfrequency 1/f-type noise properties are studied in representative mainstream material systems. It is shown that the overall noise floor is tailorable by the proper material choice, as demonstrated by the order-of-magnitude smaller noise levels in Ta 2 O 5 and Nb 2 O 5 transition-metal oxide memristors compared to Ag-based devices. Furthermore, the variation of the resistance states allows orders-ofmagnitude tuning of the relative noise level in all of these material systems. This behavior is analyzed in the framework of a point-contact noise model highlighting the possibility for the disorder-induced suppression of the noise contribution arising from remote fluctuators. These findings promote the design of multipurpose resistive switching units, which can simultaneously serve as analog-tunable memory elements and tunable noise sources in probabilistic computing machines.