High efficiency and responsivity universal silicon modulator and detector for the O-band

Area of Science:

• Photonics and Optical Engineering
• Integrated Optics
• Semiconductor Devices

Background:

• Silicon microring resonators are crucial for optical communication.
• Existing devices often require separate modulators and photodetectors, increasing complexity and footprint.
• Integrating modulation and detection functionalities is key to advancing photonic integrated circuits.

Purpose of the Study:

• To develop a single silicon microring resonator with dual functionality for modulation and photodetection.
• To characterize the device's performance in both electro-optic modulation and opto-electronic detection.
• To assess the device's potential for reducing complexity in silicon transceivers.

Main Methods:

• Fabrication of an O-band all-silicon microring resonator utilizing an L-shaped depletion-type PN junction.
• Characterization of electro-optic modulation performance, including 3-dB bandwidth and modulation efficiency.
• Evaluation of photodetection capabilities, including responsivity and opto-electronic 3-dB bandwidth under various bias conditions and photon-assisted tunneling (PAT).

Main Results:

• Achieved a 55 GHz electro-optic 3-dB bandwidth and 4.2 V·mm modulation efficiency.
• Demonstrated a peak responsivity of 0.97 A/W in avalanche mode with PAT.
• Obtained a 25 GHz opto-electronic 3-dB bandwidth at -5.5 V bias.
• Showcased performance comparable to dedicated silicon modulators and photodetectors.

Conclusions:

• The developed universal silicon microring resonator integrates high-speed modulation and high-sensitivity photodetection.
• This dual-functionality significantly reduces the number of device types and area in silicon transceivers.
• The device is a promising building block for high-bandwidth-density wavelength-division multiplexing (WDM) links and programmable photonic integrated circuits.