Compact and electrically driven active mode-locked laser at 10 GHz repetition rate based on a graphene...

Area of Science:

• Photonics
• Materials Science
• Optical Engineering

Background:

• Mode-locked lasers are crucial for high-speed optical communications and precise timing.
• Existing technologies often face limitations in size, stability, or repetition rate.
• Graphene's unique optoelectronic properties offer potential for next-generation photonic devices.

Purpose of the Study:

• To demonstrate an actively mode-locked laser using a graphene electro-absorption modulator on a photonic integrated circuit.
• To achieve high repetition rates and stable pulse generation at telecom wavelengths.
• To evaluate the performance of the integrated graphene device against established technologies.

Main Methods:

• Fabrication of a graphene electro-absorption modulator integrated onto a photonic circuit.
• Integration into a dispersion-engineered laser cavity with III-V semiconductor optical amplifiers.
• Characterization of the laser's output, including repetition rate, pulse width, and jitter.

Main Results:

• Stable generation of 10 GHz pulse trains.
• Achieved deconvoluted pulse widths of 2.9 ps.
• Demonstrated performance comparable to commercial lithium niobate modulators.

Conclusions:

• The integrated graphene-based device enables compact and stable mode-locked laser operation.
• This technology holds significant promise for realizing high-repetition-rate optical clocks.
• Graphene electro-absorption modulators are a viable alternative for high-speed photonic applications.