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 stimulated Brillouin scattering in symmetric double stripe TriPleX, shown in inset

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.

The article can be publicly accessed on the Science Advances website. Further information can be found on the University of Twente website.