Abstract: Described herein are an apparatus, system, and method for providing a vertical optical coupler (VOC) for planar photonics circuits such as photonics circuits fabricated on silicon-on-insulator (SOI) wafers. In one embodiment, the VOC comprises a waveguide made from a material having refractive index in a range of 1.45 to 3.45, the waveguide comprising: a first end configured to reflect light nearly vertical by total internal reflection between the waveguide and another medium, a second end to receive the light for reflection, and a third end to output the reflected light. The VOC couples with a Si waveguide having a first region including: a first end to receive light; and an inverted tapered end in the direction of light propagation to output the received light, wherein the inverted tapered end of the Si waveguide is positioned inside the waveguide.

Abstract: A photonic integrated circuit (I/C) includes a focusing sidewall or in-plane surface that redirects and focuses light from a waveguide to a photodetector structure. The focusing includes redirecting an optical signal to a width smaller than a width of the waveguide. The focusing of the light allows the photodetector structure to be outside a waveguide defined by parallel oxide structures. With the photodetector structure outside the waveguide, the contacts can be placed closer together, which reduces contact resistance.

Abstract: Devices comprised of end-on waveguide-coupled photodetectors are described. In embodiments of the invention, the photodetectors are avalanche photodiodes coupled end-on to a waveguide. The waveguide includes an insulating trench proximate to the coupled photodetector. In embodiments of the invention, the avalanche photodiodes are silicon/germanium avalanche photodiodes.

Abstract: Devices comprised of end-on waveguide-coupled photodetectors are described. in embodiments of the invention, the pbotodetectors are avalanche photodiodes coupled end-on to a waveguide. The waveguide comprises an insulating trench proximate to the coupled photodetector. In embodiments of the invention, the avalanche photodiodes are silicin/germanium avalanche photodiodes.

Abstract: A photonic integrated circuit (I/C) includes a focusing sidewall or in-plane surface that redirects and focuses light from a waveguide to a photodetector structure. The focusing includes redirecting an optical signal to a width smaller than a width of the waveguide. The focusing of the light allows the photodetector structure to be outside a waveguide defined by parallel oxide structures. With the photodetector structure outside the waveguide, the contacts can be placed closer together, which reduces contact resistance.

Abstract: Described herein are an apparatus, system, and method for providing a vertical optical coupler (VOC) for planar photonics circuits such as photonics circuits fabricated on silicon-on-insulator (SOI) wafers. In one embodiment, the VOC comprises a waveguide made from a material having refractive index in a range of 1.45 to 3.45, the waveguide comprising: a first end configured to reflect light nearly vertical by total internal reflection between the waveguide and another medium, a second end to receive the light for reflection, and a third end to output the reflected light. The VOC couples with a Si waveguide having a first region including: a first end to receive light; and an inverted tapered end in the direction of light propagation to output the received light, wherein the inverted tapered end of the Si waveguide is positioned inside the waveguide.