Monolithically Integrated Laser-Nonlinear Photonic Devices

Typically, a laser fabricated on a chip is connected via fiber or chip-to-chip coupling to a non-linear photonic device (e.g. frequency comb generator) to generate the desired output frequencies in response to an input provided by the laser. This method increases the size, cost and power consumption of the non-linear photonic device. It would be beneficial to integrate lasers and non-linear photonic devices on a simple integrated circuit. Using semiconductor materials as a platform of the device overcomes some of the limitations of non-linear materials, but there are still waveguide losses that pose an obstacle.

Researchers at the University of California, Santa Barbara have developed monolithically integrated non-linear photonic devices with a high quality factor, compact mode volume and ultra-efficient comb generation by leveraging a novel insulator platform. This ultra-low loss AlGaAs-on-insulator platform with anomalous dispersion and quality factors beyond 1.5 x 106 along with the high nonlinear coefficient and the small mode volume to enable a record low Kerr frequency comb generation threshold of approximately 36µW for a resonator with a 1 THz free spectral range (FSR). This result is approximately 100 times lower power consumption than previous instances of a semiconductor-on-insulator platform.