Two-color Semiconductor Mode-locked Laser system for Multiphoton Imaging Applications

Area of Science:

• Optics and Photonics
• Semiconductor Lasers
• Ultrafast Lasers

Background:

• Mode-locked lasers are essential for generating ultrashort optical pulses.
• Semiconductor optical amplifiers offer a compact and efficient gain medium for laser systems.

Purpose of the Study:

• To demonstrate an all-semiconductor mode-locked laser system.
• To achieve synchronized dual-wavelength picosecond pulse generation.
• To enable high peak power densities for nonlinear optical applications.

Main Methods:

• Utilized two external cavity mode-locked lasers.
• Employed semiconductor optical amplifiers as gain media.
• Achieved synchronized pulse trains at 834 nm and 974 nm.

Main Results:

• Generated picosecond pulses with average powers of 25 mW and 60 mW.
• Achieved peak powers exceeding 100 W and 80 W.
• Demonstrated a relative timing jitter of 7.3 ps for synchronized pulses at 282 MHz.
• Obtained TEM₀₀ mode profile with fiber-coupled output.
• Achieved peak power densities >1 GW/cm² by focusing the beam to a 4 μm spot.

Conclusions:

• The all-semiconductor mode-locked laser system provides a robust platform for generating synchronized dual-wavelength picosecond pulses.
• The high peak power densities achieved are suitable for exciting optical nonlinearities.
• This technology has potential applications in nonlinear optics, spectroscopy, and optical communications.