  Reservoir Computing is a novel computing paradigm which uses a nonlinear
recurrent dynamical system to carry out information processing. Recent
electronic and optoelectronic Reservoir Computers based on an architecture with
a single nonlinear node and a delay loop have shown performance on standardized
tasks comparable to state-of-the-art digital implementations. Here we report an
all-optical implementation of a Reservoir Computer, made of off-the-shelf
components for optical telecommunications. It uses the saturation of a
semiconductor optical amplifier as nonlinearity. The present work shows that,
within the Reservoir Computing paradigm, all-optical computing with
state-of-the-art performance is possible.
