Halide perovskite volatile unipolar nanomemristor

Halide perovskites is a recently emerged platform for the creation of efficient memristors. In turn, single-crystal inorganic perovskite would be new low-cost and flexible memory devices because of their excellent resistive switching (RS) properties, without risk of chemical and mechanical stress-generated degradation, compared with the operational instability of general thin-film perovskite memristors. Moreover, miniaturization of perovskite memristors would be useful for creating high-density memory devices. Here we demonstrate the smallest CsPbBr₃ perovskite nanomemristor with volatile unipolar RS characteristics which depends on the size of a single-crystal as a resistive layer due to its overall structural stability and low sensitivity to atmosphere conditions that helps to keep the stable RS switching over 1500 times with the lowest consumption power of 70 nW. To better understand the RS mechanism, we provide a comprehensive simulation of the evolution of mixed ionic-electronic charge carriers under current-voltage (I-V) tests using a one-dimensional drift-diffusion model. Because of the nonreactive nature of the contacts, the main mechanism of resistive state switching is potential barrier modulation of the Schottky contacts through the accumulation of migrating ions at the interfaces. Our findings pave the way for ultracompact memristors as well as shed light on RS mechanism in non-filamentary perovskite-based memory devices.