  We propose an arresting scheme for emulating the famous Faraday effect in
ultracold atomic gases. Inspired by the similarities between the light field
and bosonic atoms, we represent the light propagation in medium by the atomic
transport in accompany of the laser-atom interaction. An artificial
magneto-optic Faraday effect is readily signaled by the spin imbalance of
atoms, with the setup of laser fields offering a high controllability for
quantum manipulation. The present scheme is really feasible and can be realized
with existing experimental techniques of ultracold atoms. It generalizes the
crucial concept of the magneto-optic Faraday effect to ultracold atomic
physics, and opens a new way of quantum emulating and exploring the
magneto-optic Faraday effect and associated intriguing physics.
