We demonstrate stimulated Brillouin scattering lasing in a strongly coupled microcavity
system. By coupling two silica toroid microcavities, we achieve large mode splitting of 11
GHz, whose frequency separation matches the Brillouin frequency shift of silica. The
stimulated Brillouin scattering light is resonantly amplified by pumping at the higher
frequency side of the supermode splitting resonance. Since the mode splitting is adjusted by
changing the gap distance between the two cavities, our system does not require precise …