Stimulated Brillouin Review: Invented 50 Years Ago and Applied Today

Figure 15

Demonstration of SBS-induced transparency in a micro-resonator. Top: Theory of Brillouin signal versus probe frequency; a probe at Stokes wavelength experiences gain, while loss is predicted for a probe signal at the anti-Stokes frequency. At high excitation levels, induced transparency is expected exactly on the Brillouin resonance. Bottom: when the phonon is long-lived, loss is observed at the Stokes frequency, while a probe at the anti-Stokes frequency experiences the predicted SBS-induced transparency [adapted from [18]].