Dynamic control of light beams in second harmonic generation.

Area of Science:

• Nonlinear Optics
• Laser Physics
• Photonics

Background:

• Second harmonic (SH) generation is a key nonlinear optical process.
• Controlling the spatial properties of generated beams is crucial for applications.
• Existing methods often require complex setups or pre-fabrication.

Purpose of the Study:

• To present a novel method for dynamic 2D spatial beam shaping of SH beams.
• To achieve beam shaping by controlling the input fundamental beam's phase.
• To demonstrate the versatility of the method for different crystal lengths.

Main Methods:

• Utilizing the phase of the input fundamental beam to control the transverse phase of the SH beam.
• Employing simulations and experimental validation.
• Applying genetic algorithms to solve the inverse phase problem for longer crystals.

Main Results:

• Successfully demonstrated dynamic 2D spatial shaping of SH beams.
• Confirmed the method's effectiveness for both short and long nonlinear crystals.
• Showcased that the SH beam's transverse phase is doubled relative to the fundamental beam's phase in short crystals.

Conclusions:

• A new, dynamic method for 2D beam shaping in nonlinear optical processes has been developed.
• The technique relies on controlling the input fundamental beam's phase, not post-crystal optics.
• This approach offers a flexible and equipment-efficient way to tailor SH beam profiles.