Ultrasensitive solar-blind ultraviolet detection and optoelectronic neuromorphic computing using α-In2Se3 phototransistors

Detection of solar-blind ultraviolet (SB-UV) light is important in applications like confidential communication, flame detection, and missile warning system. However, the existing SB-UV photodetectors still show low sensitivities. In this work, we demonstrate the extraordinary SB-UV detection performance of alpha-In2Se3 phototransistors. Benefiting from the coupled semiconductor and ferroelectricity property, the phototransistor has an ultraweak detectable power of 17.85 fW, an ultrahigh gain of 1.2 x 10(6), a responsivity of 2.6 x 10(5) A/W, a detectivity of 1.3 x 10(16) Jones and an ultralow noise-equivalent-power of 4.2 x 10(-20) W/Hz(1/2) for 275 nm light. Its performance exceeds most other UV detectors, even including commercial photomultiplier tubes and avalanche photodiodes. It can be also implemented as an optoelectronic synapse for neuromorphic computing. A 784x300x10 artificial neural network (ANN) based on this optoelectronic synapse is constructed and demonstrated with a high recognition accuracy and good noise-tolerance for the Fashion-MNIST dataset. These extraordinary features endow this phototransistor with the potential for constructing advanced SB-UV detectors and intelligent hardware.

Automated summary

In this study, the extraordinary detection performance of alpha-In2Se3 phototransistors in solar-blind ultraviolet (SB-UV) light detection is demonstrated. It exceeds most other UV detectors and can be used as an optoelectronic synapse for neuromorphic computing.