Broadband saturable absorber for 10-fs pulse generation

Area of Science:

• Optics and Photonics
• Ultrafast Laser Technology

Background:

• Saturable absorbers are crucial for generating ultrashort laser pulses.
• Achieving sub-10-femtosecond (fs) pulse durations requires broadband optical components.
• Titanium-sapphire (Ti:sapphire) lasers are workhorses for ultrafast science.

Purpose of the Study:

• To fabricate and characterize a novel broadband saturable absorber.
• To investigate the potential of the absorber for generating sub-10-fs pulses.
• To demonstrate self-starting mode-locking with the developed saturable absorber.

Main Methods:

• Fabrication of a saturable absorber incorporating a silver bottom mirror.
• Characterization of the absorber's reflectivity bandwidth.
• Implementation with a Ti:sapphire laser system for mode-locking experiments.

Main Results:

• Demonstrated a broadband saturable absorber with a silver bottom mirror.
• The absorber's reflectivity bandwidth indicates potential for sub-10-fs pulse generation.
• Achieved self-starting Kerr-lens mode-locked pulses as short as 10 fs.
• Obtained self-starting soliton mode-locked pulses of 16 fs across the full cavity stability regime.

Conclusions:

• The fabricated broadband saturable absorber is suitable for generating ultrashort laser pulses.
• The device facilitates self-starting mode-locking in Ti:sapphire lasers.
• The technology holds promise for advancing ultrafast spectroscopy and nonlinear optics.