A HfS₂-based photoelectronic synaptic transistor with tunable synaptic plasticity for emotional memory

Neuromorphic computing has attracted great attention to mimic the human brain functions of perception, learning, and memory, which is considered to overcome the “von Neumann bottleneck”. Here, we developed a HfS₂-based photoelectronic field effect transistor with a tunable synaptic plasticity. By modulating the gate voltages, the paired-pulse plasticity undergoes a transition between paired-pulse facilitation (PPF = 128%) and paired-pulse depression (PPD = 89%) due to the charge-trapping effect under a pulsed light (λ = 405 nm). In a further step, five emotion valences and emotion-related learning and memories are successfully mimicked based on the various artificial synaptic metaplasticity of the HfS₂-based synaptic devices. This work provides an alternative approach to modulate the synaptic plasticity of artificial synaptic transistors for emotional memory and a new strategy to improve brain-like simulations of neuromorphic computing.