Wavelength and Polarization Sensitive Synaptic Phototransistor Based on Organic n-type Semiconductor/Supramolecular J-Aggregate Heterostructure

Abstract

Human retina-and brain-inspired optoelectronic synapses, which integrate light detection and signal memory functions for data processing, have significant interest because of their potential applications for artificial vision technology. In nature, many animals such as mantis shrimp use polarized light information as well as scalar information including wavelength and intensity; however, a spectropolarimetric organic optoelectronic synapse has been seldom investigated. Herein, we report an organic synaptic phototransistor, consisting of a charge trapping liquid-crystalline perylene bisimide J-aggregate and a charge transporting crystalline dichlorinated naphthalene diimide, that can detect both wavelength and polarization information. The device shows persistent positive and negative photocurrents under low and high voltage conditions, respectively. Furthermore, the aligned organic heterostructure in the thin-film enables linearly polarized light to be absorbed with a dichroic ratio of 1.4 and 3.7 under transverse polarized blue and red light illumination, respectively. These features allow polarized light sensitive postsynaptic functions in the device. Consequently, a simple polarization imaging sensor array is successfully demonstrated using photonic synapses, which suggests that a supramolecular material is an important candidate for the development of spectropolarimetric neuromorphic vision systems.

Optical and electronic properties of different thin-film polymorphs of PDIF-CN2 controlled by zone-casting conditions

“…For molecular thin films and devices, e.g. , for polarization-sensitive photodetectors or phototransistors where strongly polarized J-like optical properties are desired, 69 the twisted “sandwich” structure is a promising candidate.…”

“…The proposed structure for polymorph B emphasizes that the twisted ''sandwich'' structure is another possible target for crystal engineering in addition to the conventional ''headto-tail'' motif. For molecular thin films and devices, e.g., for polarization-sensitive photodetectors or phototransistors where strongly polarized J-like optical properties are desired, 69 the twisted ''sandwich'' structure is a promising candidate.…”

Recent advances in fabrication and functions of neuromorphic system based on organic field effect transistor

“…N-type organic semiconductor materials have also been investigated for neuromorphic OFET devices, and n-type OFET devices are essential for the all-organic complementary circuits [59][60][61]. Xie et al reported an n-type neuromorphic OFET device with the all-solid-state vertical structure, while the PEO/LiClO4 material functioned as the gate dielectric layer and naphthylene-1,4,5,8-tetracarboxylic-diimidethiophene-vinyl-thiophene (NDI-gTVT) as the organic semiconductor layer, whose schematic structure is illustrated as figure 2(b) [60].…”

Towards Artificial Visual Sensory System: Organic Optoelectronic Synaptic Materials and Devices

“…To mimic this polarization‐perceptual vision, Kim et al. inserted J‐aggregate PBI‐1 with a supramolecular core–shell structure into the device as a charge‐trapping layer [23] . The liquid‐crystalline J‐aggregate properties induced preferentially oriented OSC film to exhibit both wavelength‐ and polarization‐dependent synaptic properties.…”