De-coherent parallel laser processing of ultradense nanopores for high-density, large-area 3D optical phase encoding

Area of Science:

• Optics and Photonics
• Materials Science
• Nanotechnology

Background:

• Single-beam femtosecond lasers enable sub-diffraction limit modifications.
• Multi-beam parallel processing is hindered by the diffraction limit (~λ/2).
• Existing methods suffer from crosstalk and non-uniformity due to spatial coherence and temporal interference.

Purpose of the Study:

• To overcome the diffraction limit in multi-beam parallel laser writing.
• To enable ultra-dense fabrication of nanostructures.
• To achieve high-density 3D phase and polarization coding.

Main Methods:

• Proposed a de-coherent parallel direct laser writing (Dc-PDLW) strategy.
• Utilized a patterned single pulse and a de-coherent holographic algorithm (SSP-BM).
• Ensured multi-foci polarization orthogonality and eliminated spatial coherence.

Main Results:

• Achieved single-shot fabrication of ultra-dense nanopore arrays with 300 nm (~λ/4) resolution in crystals.
• Demonstrated centimeter-scale 3D Pancharatnam-Berry phase plates.
• Realized high-density 3D phase and polarization coding.

Conclusions:

• The Dc-PDLW strategy effectively overcomes diffraction limitations for parallel processing.
• This method enables high-resolution, high-density 3D nanostructure fabrication.
• The technology has potential applications in advanced optical components and data storage.