Ultrafast diode-pumped Ti:sapphire laser with broad tunability

Area of Science:

• Laser physics
• Ultrafast optics
• Materials science

Background:

• Ti:sapphire lasers are crucial for generating ultrashort pulses.
• Mode-locking techniques are essential for achieving femtosecond pulse durations.
• Combining different mode-locking methods can enhance laser performance.

Purpose of the Study:

• To develop a broadly tunable femtosecond diode-pumped Ti:sapphire laser.
• To investigate the performance of semiconductor saturable absorber mirror (SESAM) and Kerr-lens mode-locking (KLM) techniques in this laser system.
• To achieve high output power and short pulse durations across a wide wavelength range.

Main Methods:

• Passive mode-locking using both SESAM and KLM techniques.
• Diode-pumping the Ti:sapphire gain medium with 450 nm laser diodes.
• Characterization of output power, pulse duration, and wavelength tunability.

Main Results:

• SESAM mode-locking yielded up to 433 mW average output power with 62 fs pulses and 37 nm tunability (788-825 nm).
• KLM mode-locking achieved up to 382 mW average output power with 54 fs pulses and 120 nm tunability (755-875 nm).
• Broad wavelength tunability was demonstrated in both mode-locking regimes.

Conclusions:

• The developed Ti:sapphire laser offers broad wavelength tunability and high performance.
• Both SESAM and KLM techniques are effective for femtosecond pulse generation in this laser system.
• This laser system is suitable for various applications requiring tunable ultrashort pulses.