Ultrafast Responsive and Low‐Energy‐Consumption Poly(3‐hexylthiophene)/Perovskite Quantum Dots Composite Film‐Based Photonic Synapse

Abstract

Emulation of photonic synapses through photo-recordable devices has aroused tremendous discussion owing to the low energy consumption, high parallel, and fault-tolerance in artificial neuromorphic networks. Nonvolatile flash-type photomemory with short photo-programming time, long-term storage, and linear plasticity becomes the most promising candidate. Nevertheless, the systematic studies of mechanism behind the charge transfer process in photomemory are limited. Herein, the physical properties of APbBr 3 perovskite quantum dots (PQDs) on the photoresponsive characteristics of derived poly(3-hexylthiophene-2,5-diyl) (P3HT)/PQDs-based photomemory through facile A-site substitution approach are explored. Benefitting from the lowest valance band maximum and longest exciton lifetime of FAPbBr 3 quantum dot (FA-QDs), P3HT/FA-QDs-derived photomemory not only exhibits shortest photoresponsive characteristic time compared to FA 0.5 Cs 0.5 PbBr 3 quantum dots (Mix-QDs) and CsPbBr 3 quantum dots (Cs-QDs) but also displays excellent ON/OFF current ratio of 2.2 upon an extremely short illumination duration of 1 ms. Moreover, the device not only achieves linear plasticity of synapses by optical potentiation and electric depression, but also successfully emulates the features of photon synaptic such as pair-pulse facilitation, long-term plasticity, and multiple spikedependent plasticity and exhibits extremely low energy consumption of 3 × 10 −17 J per synaptic event.

Recent Advances in Organic Phototransistors: Nonvolatile Memory, Artificial Synapses, and Photodetectors

“…Notably, the FA‐QDs/P3HT photosynaptic transistor exhibited an ultralow energy consumption of 3 × 10 −17 J with EPSC = 1.210 −12 A collected at a V DS of −5 × 10 −4 V and a spike pulse of 5 × 10 −2 s under illumination at 450 nm; this represents state‐of‐the‐art artificial synapse behavior with the lowest energy consumption reported to date. [ 127 ] Subsequently, Ercan et al demonstrated the efficacy of self‐assembled nanostructures in photosynaptic transistors composed of CsPbBr 3 QDs and P3HT. [ 128 ] By introducing marginal solvent of acetonitrile, ultrasonication, and UV treatment to the blending solution of QDs and P3HT, QDs formed aligned coaggregates along with the nanofibrillar P3HT, thereby achieving a decent synaptic performance of a low energy consumption of 1.8 × 10 −16 J with EPSC = 3.6 × 10 −11 A collected at V DS of −0.001 V and a spike pulse of 5 × 10 −2 s under illumination at 450 nm to the previous result.…”

“…[ 128 ] By introducing marginal solvent of acetonitrile, ultrasonication, and UV treatment to the blending solution of QDs and P3HT, QDs formed aligned coaggregates along with the nanofibrillar P3HT, thereby achieving a decent synaptic performance of a low energy consumption of 1.8 × 10 −16 J with EPSC = 3.6 × 10 −11 A collected at V DS of −0.001 V and a spike pulse of 5 × 10 −2 s under illumination at 450 nm to the previous result. It is worth noting that CsPbBr 3 QD presents lower charge transfer efficiency to P3HT than FAPbBr 3 QDs based on the time‐resolved photoluminescent characteristics, [ 127 ] and therefore, further advancement is expected to be achieved by combining high‐performance QDs and nanostructured engineering to the semiconductors and photogates.…”

High‐Performance Non‐Volatile Flash Photomemory via Highly Oriented Quasi‐2D Perovskite

“…The programming state by photo-writing can be electronically erased by applying a gate bias (V GS ) at −60 V for 1 s and the transfer curve can shift back to initial state due to electrons neutralized by the injected holes. In order to further explain the photon-writing phenomena, the temporal drain current (I DS ) under blue light To further clarify the dynamics of photo-induced charge transfer process for all BCP/perovskite composite films, the photo-responsive current toward time was executed and described by Equation (5).…”

“…Compared to electrically programmed memories, nonvolatile flash photomemory using photon as the firth terminal can store the light information to provide noncontact writing method that simplifies the design of integrated circuit. [1][2][3][4][5] Basically, the photomemory has the same architecture as the floating-gate memory whereas the photoactive and charge-trapping material as a substitute for conventional floating-gate to enable photo-programming capability. Photo-programming process possess phase separation due to the covalent links between two segments, leading to form a variety of ordered nanostructures such as lamellas, cylinders, and spheres by controlling the block ratio or the embedded small molecules.…”

Recent Progress in Conducting Polymer Composite/Nanofiber-Based Strain and Pressure Sensors

“…Pressure sensors respond intelligently with the electrical signals in response to the applied pressure. Pressure sensors have been developed into a multidisciplinary field of research, as they interconnect material synthesis, processing, fabrication, system engineering, and signal acquisition, including new technological upgrades such as artificial intelligence and the internet of thing [58][59][60]. Recent trends and a good deal of research interests have evolved with the active involvement of metallic nanostructures, metallic hybrids, carbonaceous material-based sensing, etc., [61][62][63].…”