Precision control of carrier-envelope phase in grating based chirped pulse amplifiers

Area of Science:

• Ultrafast lasers
• Nonlinear optics
• Quantum optics

Background:

• Carrier-envelope (CE) phase stabilization is crucial for precision measurements and advanced applications of ultrafast laser systems.
• Existing methods for CE phase stabilization often involve complex setups or post-compression phase adjustments.

Purpose of the Study:

• To demonstrate a robust method for stabilizing the carrier-envelope (CE) phase of ultrafast laser pulses from a grating-based chirped pulse amplification system.
• To achieve long-term CE phase stability and precise control over the relative CE phase.

Main Methods:

• Utilized a grating-based stretcher and compressor in a high-power ultrafast laser system.
• Implemented a feedback control loop adjusting the grating separation within the stretcher to stabilize the CE phase.
• Employed a CE-phase meter, measuring electron asymmetry from above-threshold ionization, to confirm stabilization.

Main Results:

• Achieved carrier-envelope (CE) phase stabilization with a root mean square (rms) value of 180 mrad over nearly 2 hours.
• Demonstrated long-term CE phase stability comparable to systems using glass-block stretchers and prism compressors.
• Showcased the ability to lock the relative CE phase to arbitrary values within a 2π range by adjusting grating separation.

Conclusions:

• Feedback control of grating separation in a stretcher offers an effective and stable method for CE phase stabilization in grating-based chirped pulse amplification systems.
• This technique provides superior control over the relative CE phase compared to post-compression adjustment methods.
• The demonstrated stability and tunability of the CE phase open possibilities for advanced applications requiring precise phase control.