Intracavity Brillouin Gain Characterization

Brillouin gain coefficient is usually evaluated using well-established pump-probe technique. We report a technique based upon the cavity ringdown method that enables to characterize this fundamental parameter directly in a Brillouin laser cavity. Indeed, within a unique experimental setup, material gain, optical cavity parameters and laser properties can be extracted. This method would be particularly suitable for micro-resonator lasers intracavity material Brillouin gain determination.