Photonic Synapse of CrSBr/PtS₂ Transistor for Neuromorphic Computing and Light Decoding

Field effect transistors based on 2D layered material have gained significant potential in emerging technologies, such as neuromorphic computing and ultrafast memory response for artificial intelligence applications. This study proposes a facile approach to fabricate an optoelectronic artificial synapse for neuromorphic computing and light-decoding information system by utilizing the 2D heterostructure of CrSBr/PtS₂ to overcome circuit complexity. The CrSBr layer serves as a trapping layer, while PtS₂, mounted on top of CrSBr, acts as a channel layer. PtS₂ exhibits n-type semiconductor behavior with a hysteresis that varies with the thickness of the underlying CrSBr layer. The heterostructure device, featuring a 96.3 nm thick CrSBr layer, exhibited a large memory window of 11.9 V when the gate voltage is swept from −10 V to +10 V. Various synaptic behaviors are effectively demonstrated, including paired-pulse facilitation, excitatory postsynaptic current, optical spike number and intensity-dependent plasticity using laser light at a wavelength of 365 nm. The device achieves 26 distinct output signals depending on the intensity of the incident laser light, ranging from 10 to 385 mW cm⁻², enabling its applications for light-decoded information security systems. Thus, the investigation presents a unique approach to artificial intelligence and cybersecurity systems.