Reconfigurable all-optical nonlinear activation functions

We experimentally demonstrate all-optical reconfigurable nonlinear activation functions in a cavity-loaded machzehnder interferometer device utilizing free-carrier dispersion effect in silicon. Our device can be flexibly programmed to generate the following functions: clamped-ReLU, sigmoid, radial-basis and softplus, which can be employed in various neuromorphic tasks. nonlinear optics, neuromorphic photonics