Conductance quantization in memristive devices with electrodeposited Prussian blue-based dielectrics

Abstract

Identifying new, scalable materials for memristive devices is critical to advance next-generation memory and neuromorphic technologies. In this context, electrodeposited Prussian Blue (PB), a mixed-valence iron hex acyanoferrate compound, is emerging as a highly promising candidate due to its low-cost synthesis, CMOS compatibility, and rich redox chemistry. Here, we report both experimental evidence and theoretical modeling of conductance quantization in memristive devices employing PB as the active dielectric layer. PB thin films were synthesized via electrodeposition and integrated into a conventional metal–insulator–metal (MIM) structure (Ag/ PB/Au), which exhibits robust and reproducible resistive switching behavior. Notably, we observe quantized conductance steps at integer and half-integer multiples of the quantum of conductance (G 0 =2e2/h), indicative of atomic-scale filament formation and ballistic electron transport. To interpret these findings, we use a quantum transport model based on the finite-bias Landauer formalism, incorporating a series resistance and a non-ideality parameter ( α ), which successfully reproduces the experimental I V characteristics. An algorithm is also introduced to extract the model parameters directly from measured data. The emergence of quantized states is attributed to the properties of PB due to its open-framework structure, mixed Fe2/Fe3 valence, and reversible ionic mobility, which allow the formation of atomic conduction channels. These results highlight the potential of PB-based memristors for multilevel memory storage and neuromorphic computing, while offering a scalable, CMOS-compatible, and sustainable materials platform.