Brillouin Scattering in Subwavelength Silicon Waveguides

Brillouin scattering has great potential for communications and quantum technology applications. Here, we propose a novel subwavelength waveguide design to achieve narrow linewidth and strong optomechanical interaction. A Stokes gain of 1.5dB is experimentally achieved in a 6mm-length waveguide with 35.5 mW of input power.