High damage threshold birefringent optical elements (e.g. waveplates) are particularly difficult to fabricate especially with arbitrarily tailored micron-scale spatial profiles. Traditionally these kinds of optical elements have required use of special materials that are often not available in either the size or the quality required.
This novel invention specifically enables the fabrication of arbitrarily tailored birefringence characteristics in nano-structured meta-surfaces on non-birefringent substrates (e.g. fused silica). The birefringent nano-structured meta-surface is produced by angled directional reactive ion beam etching through a nano-particle mask. This method enables the simultaneous tailoring of refractive index of the meta-surface layer as well as its birefringence.
Related LLNL Article: In a first, LLNL researchers create birefringent all-glass metasurface
Image Caption: SEM image of etched metasurface with angled features.
• Enables the arbitrary tailoring of the refractive index and birefringence profile of a non-birefringent substrate surface layer down to the micron level.
• Enables the simultaneous tailoring of antireflection and birefringence properties.
• Features the high damage threshold of the intrinsic substrate material.
• Resulting refractive index pattern can be wavelength and angle insensitive (unlike thin film multi-layer dielectric solutions).
• Resulting surface texture is ultra-hydrophobic and is in principle self-cleaning.
• Ability to produce arbitrarily large, but lightweight optical elements.
• Flexibility to pattern planar and non-planar surfaces.
• High power laser systems for industrial applications
• High energy lasers systems for scientific applications
Current stage of technology development: TRL 2-3