Frequency- and Time-Dependent Electrical Response of Cu/VA-MoS2 Memristors

Abstract

While two-dimensional materials like vertically aligned molybdenum disulfide (VA-MoS2) have emerged as promising candidates for next-generation memristors, their dynamic alternating current characteristics remain largely underexplored compared to static direct current (dc) operations. In this study, we systematically investigate the frequency-dependent and time-domain transient behaviors of Cu/VA-MoS2/Si memristive devices. We demonstrate that the device functions as a tunable analog low-pass filter, where the cutoff frequency can be systematically modulated via discrete nonvolatile resistance switching or continuous dc biasing. By employing a double-exponential decay model to analyze the transient discharging waveforms, we successfully decouple the underlying physical mechanisms into two distinct operational time constants. The fast dynamic component is governed by intrinsic lattice/electronic polarization and circuit resistor–capacitor delay, while the slow component is fundamentally rate-limited by interfacial reconfiguration of mobile ionic species up to 600 Hz. These fundamental physical insights bridge the critical gap between static memory operation and dynamic signal processing, providing essential guidelines for integrating two-dimensional material memristors into future reconfigurable analog and neuromorphic circuits.