Bowers "Smaller, Cheaper Integrated Photonics"
Prof. John Bowers and researchers from UCSB, Caltech, and EPFL developed a way to integrate an optical frequency comb on a silicon photonic chip
Researchers from the University of California Santa Barbara, California Institute of Technology (Caltech), and Ecole Polytechnique Fédérale de Lausanne (EPFL) developed a way to integrate an optical frequency comb on a silicon photonic chip.
Optical frequency combs are collections of equally spaced frequencies of laser light (so called because when plotted, the frequencies resemble a hair comb). They are used with integrated lasers, which can only produce one frequency at a time.
Generating combs used to require bulky and expensive equipment, but this can be now managed using the recently emerged microresonator-based soliton frequency combs, which are miniaturized frequency comb sources built on CMOS photonic chips. Using this “integrated photonics” approach, the team has developed the smallest comb generator in the world.
The system consists of a commercially available feedback laser and a silicon nitride photonic chip. “What we have is a source that generates all these colors out of one laser and one chip,” said John Bowers, Chair in Nanotechnology at UC Santa Barbara and director of the Institute for Energy Efficiency. “That’s what’s significant about this.”