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An application of deterministic aperiodic structures : Sensing with Plasmonic quasi-crystals . Ata Akatay July 24, 2009 Photonic Crystals - Romuald Houdré. Application idea. periodic media => the formation of well-defined energy gaps disordered random media
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An application of deterministicaperiodic structures : Sensing with Plasmonic quasi-crystals Ata Akatay July 24, 2009 Photonic Crystals - Romuald Houdré
Application idea periodic media => the formation of well-defined energy gaps disordered random media => the presence of localized eigenstates with high field enhancement and Q-factors deterministic aperiodic structures => Suggest solutions in between deterministic aperiodic structures « defined by the iterations of simple mathematical rules, rooted in symbolic dynamics, prime number theory and L-system inflations » Dal Negro, L. and N. N. Feng (2007)
Fibonacci quasi-periodic structures Periodic quasiperiodic absolutely continuous singular continuous Rudin–Shapiro structures Thue–Morse and aperiodic structures Dal Negro, L. and N. N. Feng (2007)
Fractal Fourier spectra Fibonacci quasi-periodic structures Thue–Morse and aperiodic structures Rudin–Shapiro structures Dal Negro, L. and N. N. Feng (2007)
Aperiodic nanoparticle chain Dal Negro, L., N. N. Feng, et al. (2008)
Transfer matrix approach valid within the dipole approximation The dipole equations of motion : In frequency domain : Simplifies to : where, and gives : Dal Negro, L. and N. N. Feng (2007)
Analysis the integrated density of states (IDS) of the chain: participation ratio yields a quantitative measure of the localization degree of the eigenstates:
Conclusion whispering-gallery (WG) mode microcavities low shifts of modal frequencies SP sensors, which benefit from high values of field intensities in the detection region broad resonance linewidths (low Q-factors), which is a limiting factor in the spectral resolution of such devices. deterministic aperiodic structures Can be designed for more flexible solutions
References • Dal Negro, L. and N. N. Feng (2007). "Spectral gaps and mode localization in Fibonacci chains of metal nanoparticles." Optics Express 15(22): 14396-14403. • Dal Negro, L., N. N. Feng, et al. (2008). "Electromagnetic coupling and plasmon localization in deterministic aperiodic arrays." Journal of Optics a-Pure and Applied Optics 10(6): -.