Organic Optoelectronic Memristor Inspired by Insect Ultraviolet Vision for Attention Mechanism Simulation

The
rapid evolution of modern technology is propelling
artificial
intelligence into a transformative phase, where visual information
processing has become a central focus. The development of new artificial
optoelectronic synapses integrating sensing and preprocessing functions
represents a transformative approach to enhancing machine vision systems’
response capabilities. Inspired by the human retina system, a novel
polymer with dual optoelectronic response and adjustable conductivity,
poly[1,2-bis(2-methyl-5-phenylthiophen-3-yl)cyclopent-1-ene-alt-1,1’-((9H-fluorene-9,9-diyl)bis(hexane-6,1-diyl))-bis(4-ferrocene-1H-1,2,3-triazole)] (PTH-Fc), is synthesized. The as-fabricated
Al/PTH-Fc/ITO device exhibited outstanding history-dependent memristive
performance with robust retention characteristics and higher device
yield. For PTH-Fc, the diarylethenes unit is the core for achieving
the function of light-triggered synaptic behavior, while the ferrocene
unit is the key for realizing the analog and multilevel “electric
modulation” function under an electric field. The multifunctional
synaptic behavior exhibited by the PTH-Fc-based device thus stems
from the synergistic mechanism of these two components: UV light first
drives the cycloisomerization of the diarylethene backbone, forming
an initial state with enhanced conjugation. This state not only directly
contributes to the photocurrent but also optimizes the local electronic
environment, allowing the adjacent ferrocene units to undergo more
efficient and stable reversible redox reactions under the drive of
an electric field (or photogenerated electric field), thereby achieving
fine and persistent modulation of the conductance state. This work
not only demonstrates the feasibility of optoelectronic synergy regulation
in simulating neural functions but also provides new materials and
new paradigms for the development of artificial optoelectronic synapses
for machine vision.