Unified physical model for negative capacitance and resistive switching in halide perovskite devices
Phys. Rev. Applied 25, 014052 – Published 22 January, 2026
DOI: https://doi.org/10.1103/95rj-v13j
Abstract
Metal halide perovskites exhibit a rich interplay between electronic and ionic dynamics, leading to diverse phenomena such as negative capacitance (NC) and resistive switching (RS). Despite their significance in photovoltaic and memristive applications, these effects are often treated independently, with no unified physical explanation. In this work, we demonstrate that NC and RS in halide perovskite devices originate from a shared mechanism: electric field–driven ion migration. Through operando impedance spectroscopy and systematic variation of perovskite dimensionality and interfaces, we identify a quantitative correlation between the onset voltage of RS and the threshold voltage of NC (Pearson correlation coefficient r = 0.91), both governed by ionic relaxation timescales. Interfacial halide accumulation induces dipolar relaxation, yielding volatile switching and NC, whereas bulk ion percolation enables nonvolatile RS through conductive filament formation. A phase diagram constructed from ion concentration and interfacial energetics delineates the transition between these regimes. This unified framework establishes the physical basis for tuning memristor volatility and provides a predictive approach for the design of ionically coupled perovskite systems.
