Experimental and First‐Principles Study of Visible Light Responsive Memristor Based on CuAlAgCr/TiO₂/W Structure for Artificial Synapses with Visual Perception

Abstract

The development of vision bionic systems is indispensable for the perception, memory, and processing of optical signals, which promotes the exploration of efficient visual perception systems. In this work, a simple and novel two‐terminal optoelectronic memristor based on the CuAlAgCr/TiO2/W (CTW) structure is prepared, where the CuAlAgCr high‐entropy alloys are employed as the top electrode for the first time. Before annealing, the CTW optoelectronic memristor exhibited fascinating performance, including uniformly distributed operating voltage, reliable data retention, and a higher switching ratio. Moreover, the optoelectronic memristor can be reversibly switched between volatile and nonvolatile memories by adjusting compliance currents. The CTW optoelectronic memristor annealed in air exhibits various artificial synaptic functions, such as short‐term memory, optical learning, and forgetting behavior under the illumination of the laser. The photo‐response current is increased from nano‐ampere to micro‐ampere level. Furthermore, a logic function unit based on CTW optoelectronic memristor is proposed, which realizes “AND” operation. Furthermore, first‐principles calculations of the CTW structure are performed to describe the influence of photocarriers on the barrier height at the CuAlAgCr‐TiO2 interface, revealing the working mechanism of the CTW optoelectronic memristor. This work has greatly facilitated the development of optically operated artificial synaptic devices and vision bionic systems.

Achieving Reliable and Ultrafast Memristors via Artificial Filaments in Silk Fibroin

“…Therefore, we have measured highresolution I-V switching curves of the Ag/SF/Au memristor (Figure 2g) and obtained an SS of less than 0.01 mV dec −1 , which is the smallest SS to the best of our knowledge (benchmarked in Figure 2h). [43][44][45][46][47][48][49][50][51][52] The pulse-mode measurement further showed a sub-100 ns resistive switching speed (Figure 2i), corresponding to a low operation energy of ≈14 pJ. The switching speed of Agbased memristors is mainly limited by the Ag ions' transport velocity in the insulating layer, which was controlled by the applied electric field.…”

Technology and Integration Roadmap for Optoelectronic Memristor

“…However, rapid recovery can be achieved through electrical processes. [226][227][228][229] This phenomenon can be leveraged to simulate synaptic behavior.…”

“…For electronic gadgets to keep up with the "More than Moore" trend, they need to diversify their functionality by adding sensors, memory, and processing units. [229,245,246,247] Optical sensing, data storage, and processing all being integrated into a single device is an essential requirement for any future energyefficient and minimized optoelectronic system due to the huge share of storage space used by images in both the core network and edge devices. [55,248] Here, we take an in-depth summarization of one of the most noteworthy newer enhancements to nanostructure-based OMs and the intelligent optoelectronic systems about the future enable artificial intelligence.…”

Logical Perception of Artificial Vision Based on Nonlinear Neuromorphic Responses of Optoelectronic Synapses

“…In addition, the current logical functions of synapses mainly focus on “AND” and “OR” operations, sometimes even under different threshold values (as detailed in Table ). − Moreover, low tolerances of logic operations are exhibited in previous research. For example, in Hou’s work, a threshold of 154 μA was used for “AND” and “OR” operations while the threshold range is extremely narrow, only between 153 and 155 μA for “AND” and “OR” operations.…”