Researchers at the University of Twente have successfully demonstrated the first guided acoustic wave produced by stimulated Brillouin scattering (SBS) in silicon nitride (SiN) using our symmetric double stripe TriPleX® chips!
SBS is a phenomenon by which light traveling through a waveguide may induce an acoustic wave in the medium. Using two opposing lasers, researchers at the Nonlinear Nanophotonics groups generated a mechanical wave capable of enacting a notch filter with high attenuation and a narrow bandwidth.
An illustration of the generation and trapping of stimulated Brillouin scattering in symmetric double stripe TriPleX®, shown in the inset.
Leakage of the acoustic wave from the waveguide core to its cladding has been a consistent hurdle to the implementation of SBS in integrated photonics. The structure of the multilayer TriPleX® waveguides allowed the researchers to contain the acoustic wave between the two SiN stripes. The containment and control of SBS let the researchers implement a notch filter, which is very useful for microwave photonic signal processing.