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Adding optical functionality to a silicon microelectronic chip is one of the most challenging problems of materials research. Silicon is an indirect-bandgap semiconductor and so is an inefficient emitter of light. For this reason, integration of optically functional elements with silicon microelectronic circuitry has largely been achieved through the use of(More)
The propagation of light in nonperiodic quasicrystals is studied by ultrashort pulse interferometry. Samples consist of multilayer dielectric structures of the Fibonacci type and are realized from porous silicon. We observe mode beating and strong pulse stretching in the light transport through these systems, and a strongly suppressed group velocity for(More)
Deterministic Aperiodic (DA) arrays of gold (Au) nanoparticles are proposed as a novel approach for the engineering of reproducible surface enhanced Raman scattering (SERS) substrates. A set of DA and periodic arrays of cylindrical and triangular Au nanoparticles with diameters ranging between 50-110 nm and inter-particle separations between 25-100 nm were(More)
Defined nanoparticle cluster arrays (NCAs) with total lateral dimensions of up to 25.4 microm x 25.4 microm have been fabricated on top of a 10 nm thin gold film using template-guided self-assembly. This approach provides precise control of the structural parameters in the arrays, allowing a systematic variation of the average number of nanoparticles in the(More)
In this paper, we combine experimental dark-field scattering spectroscopy and accurate electrodynamics calculations to investigate the scattering properties of two-dimensional plasmonic lattices based on the concept of aperiodic order. In particular, by discussing visible light scattering from periodic, Fibonacci, Thue-Morse and Rudin-Shapiro lattices(More)
The accurate and reproducible control of intense electromagnetic fields localized on the nanoscale is essential for the engineering of optical sensors based on the surface-enhanced Raman scattering (SERS) effect. In this paper, using rigorous generalized Mie theory (GMT) calculations and a combined top-down/bottom-up nanofabrication approach, we design and(More)
In this paper we investigate for the first time the near-field optical behavior of two-dimensional Fibonacci plasmonic lattices fabricated by electron-beam lithography on transparent quartz substrates. In particular, by performing near-field optical microscopy measurements and three dimensional Finite Difference Time Domain simulations we demonstrate that(More)
In this paper we study the spectral, localization and dispersion properties of dipolar modes in quasi-periodically modulated nanoparticle chains based on the Fibonacci sequence. By developing a transfer matrix approach for the calculation of resonant frequencies, oscillation eigenvectors and integrated density of states (IDS) of spatially-modulated dipole(More)
We demonstrate controllable structural color based on periodic nanopatterned 2D lattices in pure protein films of silk fibroin. We show here periodic lattices in silk fibroin films with feature sizes of hundreds of nanometers that exhibit different colors as a function of varying lattice spacing. Further, when varying the index of refraction contrast(More)
Light emission from Er-doped amorphous silicon nitride coupled to photonic crystal resonators is studied. The results demonstrate Purcell enhanced Er absorption and linewidth narrowing of the cavity resonance with increasing pump power.