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Abstract Disorder is an essential parameter in photonic systems and devices, influencing phenomena such as the robustness of topological photonic states and the Anderson localization of modes in waveguides. We develop and demonstrate a method for both analyzing and visualizing positional, size, and shape disorder in periodic structures such as photonic crystals. This analysis method shows selectivity for disorder type and sensitivity to disorder down to less than 1%. We show that the method can be applied to more complex shapes such as those used in topological photonics. The method provides a powerful tool for process development and quality control, including analyzing the precision of E-Beam Lithography before patterns are transferred; quantifying the precision limits of lithography, deposition, or etch processes; and studying the intentional displacement of individual objects within otherwise periodic arrays.
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Effect of disorder and plasmonic confinement on mode localization in disordered arrays of hybrid waveguides
We study mode localization in a quasi-one-dimensional disordered array of titanium dioxide waveguides above a silver film embedded inside a fused silica matrix. Disorder is introduced by randomly offsetting waveguides from their periodic positions by up to 20% of the array period. Using a perturbative coupled mode theory with nearest-neighbor coupling, we study how mode localization changes with increasing disorder and array size. Our results show mode localization, as measured by both the average effective mode area and variance for all modes, intensifies with increasing disorder, especially for the fundamental modes with tighter plasmonic confinement. Remarkably, we find the average variance scales with the array size, resulting in a universal dependence of normalized variance on disorder for arrays of any size. These findings may have implications for designing photonic devices and developing efficient photodetectors.
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- Award ID(s):
- 2151971
- PAR ID:
- 10569950
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Express
- Volume:
- 33
- Issue:
- 3
- ISSN:
- 1094-4087; OPEXFF
- Format(s):
- Medium: X Size: Article No. 5486
- Size(s):
- Article No. 5486
- Sponsoring Org:
- National Science Foundation
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