Integrated Photonics

Controlling photons, phonons, and nonlinearities

The Rakich Lab specializes in integrated photonic systems that harness photons, phonons, and nonlinearities to realize next-generation quantum computing, communications, sensing, and optical clock technologies. We specialize in the use of engineerable linear and nonlinear interactions based on photon-phonon couplings and electronic nonlinearities to shape and control light in photonic circuits as well as new cavity technologies that offer ultra long storage times, ultra-low noise, and enhanced light-matter coupling for classical and quantum applications.

Engineerable photon-phonon coupling: 

By tailoring photon-phonon in waveguides, we have shown that Brillouin nonlinearities become highly engineerable, enabling new on-chip optical amplifiers and lasers. Using these same interactions to transduce information between optical and acoustic domains, we have demonstrated new signal processing techniques that utilize the remarkable coherence characteristics of phonons. We have also used these interactions to realize ultra-wideband optical isolators, eliminating the need for magnetic media and addressing a critical challenge facing the field of integrated photonics. Exploiting photon-phonon interactions for quantum applications, we have also shown that laser cooling and control of long-lived phonon in the quantum regime also becomes possible when optical cavities are used to enhance the strength of photon-phonon coupling (see cavity optomechanics). 

Ultra-high-Q Integrated Photonics: 

In parallel, we develop powerful new photonics platforms that enable ultra-high performance optical cavities that support ultra-high quality factors (>10⁹) resonators and photon-lifetimes. These devices allow strong, engineered light–matter interactions in compact formats and support applications in quantum optics, atomic sensing, and laser stabilization. Through hybrid-integration such resonators with photonic circuits, we have demonstrated new ultra-low noise chip-scale lasers as the basis for communications, sensing, and time-keeping applications. Building on these concepts, we work to realize hybrid systems that enable new single-photon sources, quantum memories, leveraging phonons, atoms, and defect centers.