In photonic crystal slabs, the relevant modes are situated below the light line. Instead, for high-index-contrast gratings (HCGs), also denoted photonic crystal mirrors, the modes above the light light line play an important role by promoting interactions with free-space modes outside the slab. Thus, the HCG acts as a mirror for light injected perpendicularly to the slab. During the last few years, the physics of HCGs have been extensively studied, and novel hybrid lasers and photodetectors comprising HCGs have been experimentally realized on a silicon-on-insulator  wafer. Establishing the necessary fabrication technology has been a major effort, but recently there has been considerable experimental progress.

Schematic cross-sectional view of a hybrid vertical-cavity laser with an in-plane output waveguide, which is integrated onto a SOI wafer. (b) Top-view microscope image of a fabricated laser sample.

We work on the following topics:

• Hybrid vertical-cavity laser
• Ultrahigh-speed laser based on high-index-contrast gratings
• Hybrid grating reflector – a new type of grating reflector
• Hybrid resonant cavity photodetectors

Relevant NATEC papers:

I.-S. Chung and J. Mørk, “Silicon photonics light source realized by III-V/ Si-grating-mirror laser”, Applied Physics Letters 97, 151113 (2010).

S. Learkthanakhachon, K. Yvind, and I.-S. Chung, “Tunable resonant-cavity-enhanced photodetector with double high-index-contrast grating mirrors”, in Proceeding of SPIE, Vol. 8633 (SPIE, 2013).