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Devices with volatile memristive switching and self‐sustained relaxation oscillations have received significant attention for their use in neuromorphic computing and solving optimization problems. However, obtaining devices with stable response and reliable oscillation remains challenging. This work describes the utility of metal/oxide interlayers in achieving reliable device performance with tuneable characteristics using Nb‐Nb2O5‐Pt structures. Detailed physical characterization of the Nb/Nb2O5 interlayer region shows that it consists of a thin, near‐stoichiometric Nb2O5 and an NbOx layer with a graded oxygen content. The impact of these interlayers on device performance is assessed by investigating their switching characteristics and oscillation dynamics. It is shown that the presence of the interlayer has a direct impact on the memristive switching mode and parameters threshold switching characteristics parameters. These dependencies are explained with reference to a lumped‐element circuit model of the device and shown to be dominated by changes in device resistance caused by interlayer formation. Significantly, stable oscillation with tuneable frequency is obtained by increasing the thickness of the reactive Nb electrode. Then, by simulating an array of coupled oscillators, a unique Hamiltonian solver is demonstrated. These results provide pathways for optimizing volatile memristive switching characteristics and guidance on how such devices can be employed to solve combinatorial optimization problems. [ABSTRACT FROM AUTHOR]

We develop a tri-state memristive system based on composable binarized memristors, from both a dynamical systems construction to the development of in-house fabricated devices. Firstly, based on the SPICE model of the binary memristor, the series and parallel circuits of binary memristors are designed, and the characteristics of each circuit are analyzed in detail. Secondly, through the analysis of the connection direction and parameters of the two binary memristors, an effective method to construct a tri-state memristor is proposed, and verified using SPICE simulations. Finally, the characteristics of the constructed equivalent tri-state memristor are analyzed, and it is concluded that the amplitude, frequency and type of the input signal can affect the characteristics of the equivalent tri-state memristor. Predictions from this modeling were validated experimentally using Au/ Nb 2 O 5 /Nb cross-point devices. [ABSTRACT FROM AUTHOR]