Efficient Coupling of an Antenna-Enhanced nanoLED into an Integrated InP Waveguide

Area of Science:

• Photonics and Nanotechnology
• Integrated Optics
• Semiconductor Devices

Background:

• Traditional on-chip metal interconnects face increasing power consumption challenges.
• Optical links offer a power-efficient alternative but require efficient nanoscale light sources.
• Optical antennas can enhance the efficiency and emission rate of nanoscale optical emitters.

Purpose of the Study:

• To demonstrate an optical antenna-enhanced nanoLED coupled to an integrated waveguide.
• To address the lack of efficient, nanoscale light sources for on-chip optical interconnects.
• To achieve high coupling efficiency and directional emission into integrated photonic circuits.

Main Methods:

• Fabrication of nanoLEDs using an InGaAsP nanoridge coupled to a gold optical antenna.
• Integration of the antenna-enhanced nanoLED with a low-loss Indium Phosphide (InP) waveguide.
• Characterization of spontaneous emission rate enhancement and coupling efficiency.

Main Results:

• Demonstrated a 36x enhancement in the spontaneous emission rate of the nanoLED.
• Achieved coupling efficiencies as high as 70% into the integrated InP waveguide.
• Observed directional emission with front-to-back ratios up to 3:1 using directional antennas.

Conclusions:

• The antenna-enhanced nanoLED is a viable and efficient nanoscale light source for on-chip optical links.
• This technology overcomes previous limitations in coupling nanoscale emitters to integrated waveguides.
• The demonstrated performance paves the way for next-generation, power-efficient optical interconnects.