  We review recent advances in rectification control of artificial
microswimmers, also known as Janus particles, diffusing along narrow,
periodically corrugated channels. The swimmer self-propulsion mechanism is
modeled so as to incorporate a nonzero torque (propulsion chirality). We first
summarize the effects of chirality on the autonomous current of microswimmers
freely diffusing in channels of different geometries. In particular, left-right
and upside-down asymmetric channels are shown to exhibit different transport
properties. We then report new results on the dependence of the diffusivity of
chiral microswimmers on the channel geometry and their own self-propulsion
mechanism. The self-propulsion torque turns out to play a key role as a
transport control parameter.
