Optogenetics inspired transition metal dichalcogenide neuristors for in-memory deep recurrent neural networks

摘要

Inspiration from optogenetics. Our approach of using PENs in an artificial neural network gives us the flexibility to selectively activate either neurons or synapses. An I&F circuit is designed using two operational amplifiers and the PEN functionally mimicking optically active ion-channels in optogenetics. Without light activation, the neuron fires at a baseline rate set by the reversal potential of the artificial ion-channel. On illumination by blue light (  = 445 nm, amplitude = 5 mWcm and pulse width = 10 ms), the conductance of the PEN (G ) increases, resulting in a higher frequency of neuronal firing (top). An I&F neuron constructed using conventional resistors does not show any change in firing rate on optical stimulation (bottom). Photo-modulated spike-timing-dependent plasticity learning rules in PENs. The graphs (read row-wise) depict the modulations of STDP upon illumination with red (623 nm), green (525 nm) and blue (445 nm) light with an intensity = 230 mWcm .