Low-Power Bidirectional Threshold Switching Characteristics of Ambient-Stable Rb₁₈Cu₃₁Cl₄₉─Poly(methyl methacrylate) Composite Memristor Devices

Threshold-switching memristors are currently of intense importance owing to their ability to mimic biological neurons and synapses by utilizing simple circuitry. Here, we report on the synthesis of a rubidium copper chloride (Rb18Cu31Cl49, RCC) inorganic compound for the fabrication of a memristor device. The composite fabricated with RCC and a poly(methyl methacrylate) compound in a metal–insulator–metal (MIM) structure memristor device shows threshold switching behavior. The device exhibits bidirectional as well as multilevel threshold switching characteristics with a low threshold voltage Vth ≈ −0.5 V, +1.4 V, along with a significantly high on–off current ratio >104. A low standby power consumption (∼35 fW) with low off-state leakage current ∼10–12 A is realized from the memristor device. Minimum on-state power consumption is found to be 50 nW, demonstrating its potential toward low-power system development. Endurance tests show a wide threshold window between low and high resistive states for more than 2000 pulse cycles, while retention tests reveal robust performance for more than 2000 s. The device produces reliable bidirectional threshold switching behavior for up to ∼100 days in ambient conditions, demonstrating robust ambient stability.