Filippo Capolino

Learn More
The Ewald method is applied to accelerate the evaluation of the Green’s function (GF) of an infinite equispaced linear array of point sources with linear phasing. Only a few terms are needed to evaluate Ewald sums, which are cast in terms of error functions and exponential integrals, to high accuracy. It is shown analytically that the choice of the standard(More)
We demonstrate a novel technique to fabricate sub-micron silicon nitride waveguides using conventional contact lithography with MEMS-grade photomasks. Potassium hydroxide anisotropic etching of silicon facilitates line reduction and roughness smoothing and is key to the technique. The fabricated waveguides is measured to have a propagation loss of 0.8dB/cm(More)
We propose a design of a dielectric (silicon nitride) optical leaky wave antenna (OLWA) with periodic semiconductor (silicon) corrugations, capable of producing narrow beam radiation. The optical antenna radiates a narrow beam because a leaky wave (LW) with low attenuation constant is excited at one end of the corrugated dielectric waveguide. We show that(More)
We investigate for the first time the capacity of a twodimensional periodic array (a metasurface) of circular nanoclusters (CNCs) of plasmonic nanoparticles to support magnetic Fano resonances. These resonances are characterized by narrow angular and/or spectral features in the reflection/transmission/absorption coefficients associated with a circular(More)
| This review paper summarizes various aspects of directive beaming and explains these aspects in terms of leaky waves. Directive beaming occurs in antenna design where a narrow beam is obtainable by using fairly simple planar structures excited by a single source. These structures include Fabry–Pérot cavity structures as well as metamaterial structures(More)
We show that the enhanced directivity phenomenon for light passing through a subwavelength aperture in a silver film with corrugations on the exit face, is due to a leaky wave that decays exponentially from the aperture. We show quantitatively that the field along the interface of the silver film is dominated by the leaky wave, and that the radiation of the(More)
Near-field plasmonic coupling and local field enhancement in metal nanoarchitectures, such as arrangements of nanoparticle clusters, have application in many technologies from medical diagnostics, solar cells, to sensors. Although nanoparticle-based cluster assemblies have exhibited signal enhancements in surface-enhanced Raman scattering (SERS) sensors, it(More)
This Letter presents a study of the local density of states (LDOS) in photonic quasicrystals. We show that the LDOS of a Penrose-type quasicrystal exhibits small additional band gaps. Among the band gaps, some exhibit a behavior similar to that typical of photonic crystals, while others do not. The development of certain band gaps requires large-size(More)
Benefiting from aggressive feature size scaling, silicon technologies have recently shown the capability of implementing W-band imaging receivers with an image resolution of 1.5mm and temperature resolutions of less than 0.5K [1-4]. This paper extends the capability of an imaging array receiver by improving image resolution using the novel concept of(More)