Mode locking of a continuous-wave titanium-doped sapphire laser using a linear external cavity

Area of Science:

• Laser physics
• Ultrafast optics
• Materials science (Titanium-sapphire)

Background:

• Mode locking is crucial for generating ultrashort laser pulses.
• Traditional methods often require complex active or nonlinear elements.
• Titanium-sapphire (Ti:Al2O3) lasers are known for their tunability and broad gain bandwidth.

Purpose of the Study:

• To describe a novel mode-locking technique for Ti:Al2O3 lasers.
• To demonstrate ultrashort pulse generation without active or nonlinear components.
• To investigate the underlying mechanism of this passive mode-locking method.

Main Methods:

• Utilizing a continuous-wave (cw) Ti:Al2O3 laser.
• Incorporating a moving extracavity mirror.
• Operating without active mode-locking devices or nonlinear external elements.

Main Results:

• Direct generation of ultrashort laser pulses.
• Achieved pulse durations of less than 40 picoseconds.
• Demonstrated a novel passive mode-locking mechanism.

Conclusions:

• A simple and effective method for passive mode locking in Ti:Al2O3 lasers has been developed.
• The moving extracavity mirror technique offers an alternative to complex mode-locking setups.
• Further investigation into the pulse generation mechanism is warranted.