Three dimensional laser microfabrication in diamond using a dual adaptive optics system

Area of Science:

• Materials Science
• Optics
• Laser Physics

Background:

• Femtosecond laser fabrication enables precise material modification.
• Achieving controlled 3D structures deep within materials like diamond is challenging due to optical aberrations.
• Refractive index mismatch between diamond and immersion media significantly distorts laser beams.

Purpose of the Study:

• To demonstrate femtosecond laser fabrication of controlled 3D structures deep within diamond.
• To investigate the use of a dual adaptive optics system for aberration compensation.
• To enhance fabrication efficiency and precision at greater depths.

Main Methods:

• Utilized a dual adaptive optics system comprising a deformable mirror and a liquid crystal spatial light modulator.
• Compensated for aberrations caused by the refractive index mismatch between diamond and the objective immersion medium.
• Fabricated micron-scale features at depths exceeding 200 μm within diamond.

Main Results:

• Aberration compensation was found to be essential for controlled feature generation at depths > 200 μm.
• The dual adaptive optics system significantly improved fabrication efficiency compared to single adaptive element approaches.
• Precise micron-scale 3D structures were successfully fabricated deep within the diamond bulk.

Conclusions:

• Dual adaptive optics effectively compensates for aberrations in deep-bulk laser fabrication in diamond.
• This technique enables precise control and enhanced efficiency for creating complex 3D structures within diamond.
• The findings pave the way for advanced applications in diamond micro- and nanomachining.