Low Switching Power Neuromorphic Perovskite Devices with Quick Relearning Functionality

Abstract

In the quest to reduce energy consumption, there is a growing demand for technology beyond silicon as electronic materials for neuromorphic artificial intelligence devices. Equipped with the criteria of energy efficiency and excellent adaptability, organohalide perovskites can emulate the characteristics of synaptic functions in the human brain. In this aspect, this study designs and develops CsFAPbI3‐based memristive neuromorphic devices that can switch at low power and show larger endurance by adopting the powder engineering methodology. The neuromorphic characteristics of the CsFAPbI3‐based devices exhibit an ultra‐high paired‐pulse facilitation index for an applied electric stimuli pulse. Moreover, the transition from short‐term to long‐term memory requires ultra‐low energy with long relaxation times. The learning and training cycles illustrate that the CsFAPbI3‐based devices exhibit faster learning and memorization process owing to their larger carrier lifetime compared to other perovskites. The results provide a pathway to attain low‐power neuromorphic devices that are synchronic to the human brain's performance.

Mixed‐Halide Perovskite Memristors with Gate‐Tunable Functions Operating at Low‐Switching Electric Fields

“…at S‐D interfaces. [ 39,45,46,50,52 ] The concentration of I within the perovskite layer was reported higher in regions close to the electrode using grazing‐incidence wide‐angle X‐ray scattering adding this way an ion conduction pathway supporting the argument that I ̶ is the dominant ion in perovskite films due to its lower formation energy and higher mobility. [ 39 ]…”

“…at S-D interfaces. [39,45,46,50,52] The concentration of I within the per-ovskite layer was reported higher in regions close to the electrode using grazing-incidence wide-angle X-ray scattering adding this way an ion conduction pathway supporting the argument that I ̶ is the dominant ion in perovskite films due to its lower formation energy and higher mobility. [39] By applying an opposite bias, a reversed ion/carrier distribution is obtained by modifying the corresponding potential barrier profile along the surface of the channel (Figure 3b) leading to the HRS to LRS transition and the memristive-like I D -V D characteristics.…”

“…[37,38,43] Notably, it has been shown in 2T memristors that MA and I − have the smallest activation energy for vacancy-mediated ion migration, and furthermore, the multi-cation structure of OIHP enhances the memristive switching effects and their stability. [37,38] Possibly contribution of a filament-based mechanism that is mainly induced by iodine vacancies, I ̶ , or subsequent trapping of charges within the grain boundaries [52] cannot be excluded. For an overview of reported switching mechanisms in perovskite-based memristors and the potential contribution of halides migration, bulk perovskite defects, MA or Ag migration, the reader is redirected to Ref.…”

Charge‐Mediated Copper‐Iodide‐Based Artificial Synaptic Device with Ultrahigh Neuromorphic Efficacy

“…After each cycle, a spontaneous relaxation decay, denoted as "τ", transpired, a phase typically known as the forgetting stage. [22,44]…”