Optoelectronic Reservoir Computing Based on 2D P-Type Nb-Doped MoS₂ Field-Effect Transistor

Molybdenum disulfide (MoS₂) has drawn extensive interest due to its excellent performance as a 2D n-type semiconductor. However, achieving high-performance devices based on p-type MoS₂, which is crucial for complementary field effect transistors (CFETs) and neuromorphic computing applications, remains limited. Here, an optoelectronic reservoir computing (RC) based on a p-type Nb-doped MoS₂ device is reported. The device shows p-type transistor characteristics with a high on/off current ratio exceeding 10⁶, low subthreshold swing (SS) of 234 mV dec^-1, notable on-state current of 12 µA µm^-1, along with robust cyclic performance and ambient stability. Importantly, the optically tunable facilitated and depressed conductance arises from Nb-vacancy defect states, confirmed by Kelvin probe force microscopy measurement. Furthermore, the device enables 100% motion recognition across eight directions and functions as a reservoir to map feature information from various sequential optical inputs, exhibiting computing capability in pattern recognition with an accuracy of 88%.