Exploiting Slow Light for Stimulated Brillouin Scattering (Vol. 50, No. 3)

Stimulated Brillouin scattering (SBS) is an important third-order nonlinear process. The main challenge of utilizing SBS in silicon photonic waveguides is that the SBS gain coefficient is too weak to generate efficient power conversion between optical waves and acoustic waves.

In a recent study, the authors show how to improve the SBS process in a periodic suspended silicon waveguide by exploiting the slow light characteristic. They focus on tuning the structural parameters and working wavelength of the device to exploiting the resonance enhancement effect to amplify the weak SBS phenomenon. The calculated SBS gain coefficient is shown to be in the order of 10⁶ W^-1m^-1. They also prove the feasibility of the device design using standard silicon-on-insulator wafers. The slow-light waveguide provides a powerful platform for light-sound interaction through SBS process.

Y. Xu, L. Zhou, L. Lu, J. Chen, and B. M. A. Rahman, Enhanced forward stimulated Brillouin scattering in silicon photonic slot waveguide Bragg grating, J. Phys. D: Appl. Phys. 52, 184001 (2019)
[Abstract]