Neuron devices based on point contact phototransistors

We propose neuron devices that perform subtraction and nonlinear functions with two-input and one-output optical signals. The device based on a pair of point-contact phototransistors and a LED can easily integrated with several hundred pixels. The basic structure of the PCPT we developed is a 10 nm thickness InGaAs quantum well with GaAs barrier layers grown by molecular beam epitaxy (MBE).