Analogue summation of electrical spike trains in semiconductor nerve fibres

We fabricate and investigate electrical pulse propagation in modulation-doped semiconductor nerve fibres made of sub-micron pn wires. We report the analogue summation of electrical impulses at the junction of three or more fibres. These wires model the longitudinal conductivities of potassium and sodium ions inside and outside a nerve capillary as well as the transverse capacitance of the nerve membrane and the non-linear conductance of its ion channels. We demonstrate the summation and annihilation of electrical impulses at both 300 and 77 K, which forms the basis for making spike-timing neural networks. A comparison of experimental and theoretical parameters of pulse propagation at these two temperatures is presented. The successful implementation of artificial nerve fibres promises parallel computation devices and spiking neural networks.