Synchronization of two memristive coupled van der Pol oscillators

摘要

The objective of this paper is to explore the possibility to couple two vander Pol (vdP) oscillators via a resistance-capacitance (RC) network comprisinga Ag-TiOx-Al memristive device. The coupling was mediated by connecting thegate terminals of two programmable unijunction transistors (PUTs) through thenetwork. In the high resistance state (HRS) the memresistance was in the orderof MOhm leading to two independent selfsustained oscillators characterized bythe different frequencies f1 and f2 and no phase relation between theoscillations. After a few cycles and in dependency of the mediated pulseamplitude the memristive device switched to the low resistance state (LRS) anda frequency adaptation and phase locking was observed. The experimental resultsare underlined by theoretically considering a system of two coupled vdPequations. The presented neuromorphic circuitry conveys two essentialsprinciple of interacting neuronal ensembles: synchronization and memory. Theexperiment may path the way to larger neuromorphic networks in which thecoupling parameters can vary in time and strength and are realized bymemristive devices.