  Fizeau experiment, inspiring Einstein's special theory of relativity, reveals
a small dragging effect of light inside a moving medium. Dispersion can enhance
such light drag according to Lorentz's predication. Here we experimentally
demonstrate slow and fast light enhanced light drag in a moving optical
microcavity through stimulated Brillouin scattering induced transparency and
absorption. The strong dispersion provides an enhancement factor up to ~10^4,
greatly reducing the system size down to the micrometer range. These results
may offer a unique platform for a compact, integrated solution to motion
sensing and ultrafast signal processing applications.
