Programmable-trajectory ultrafast flying focus pulses

Area of Science:

• Optics and Photonics
• Ultrafast Laser Technology
• Applied Physics

Background:

• "Flying focus" techniques enable laser pulses with focal points that move over extended distances, surpassing the conventional Rayleigh length.
• Implementing these advanced laser techniques necessitates optical designs capable of both extending focal range and precisely controlling radial group delay.

Purpose of the Study:

• To present a novel method for designing optical configurations that generate ultrashort flying focus laser pulses.
• To enable programmable trajectories for the focal points of these ultrashort laser pulses.

Main Methods:

• Utilized an axiparabola to achieve an extended focal range.
• Employed a reflective echelon or a deformable mirror-spatial light modulator (SLM) pair to structure the radial group delay.
• Demonstrated the design method through illustrative examples.

Main Results:

• Successfully designed optical configurations capable of producing ultrashort flying focus pulses with programmable focal trajectories.
• The axiparabola effectively extended the focal range.
• The deformable mirror-SLM configuration allowed for rapid exploration and optimization of flying focus characteristics.

Conclusions:

• The proposed design method provides a pathway for creating advanced optical systems for flying focus applications.
• The demonstrated configurations offer precise control over focal point dynamics.
• The flexibility of the deformable mirror-SLM approach makes it particularly suitable for experimental optimization and future research.