Electrically pumped hybrid evanescent Si/InGaAsP lasers.

Area of Science:

• Photonics and optoelectronics
• Materials science
• Semiconductor device physics

Background:

• Hybrid silicon photonics integrates diverse materials onto silicon platforms.
• III-V semiconductors are crucial for laser gain.
• Fabry-Perot lasers are fundamental optical devices.

Purpose of the Study:

• To demonstrate hybrid silicon/III-V Fabry-Perot evanescent lasers.
• To utilize InGaAsP as the III-V gain material for the first time in this configuration.
• To characterize device performance, including threshold current, output power, and efficiency.

Main Methods:

• Fabrication of hybrid silicon/III-V Fabry-Perot evanescent laser structures.
• Integration of InGaAsP as the gain medium with silicon waveguides.
• Characterization of lasing performance under continuous wave operation.

Main Results:

• Achieved low lasing threshold current (24 mA for 300-µm devices).
• Obtained maximal single facet output power of 4.2 mW at 15°C, and up to 12.7 mW for longer devices.
• Demonstrated continuous wave operation up to 45°C with a slope efficiency of 8.4% and threshold current density of 1 kA/cm².
• Observed light largely confined to the silicon waveguide.

Conclusions:

• The developed hybrid Si/III-V lasers show promising performance exceeding previous similar devices.
• InGaAsP is an effective gain material for hybrid evanescent lasers.
• These devices represent a significant step towards efficient integrated optical sources on silicon platforms.