Luca Dal Negro

Ashwin Gopinath8
Yiyang Gong7
8Ashwin Gopinath
7Yiyang Gong
6L Dal Negro
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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)
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 explore the potential of one-dimensional and two-dimensional deterministic aperiodic plasmonic arrays for the design of electromagnetic coupling and plasmon-enhanced, sub-wavelength optical fields on chip-scale devices. In particular, we investigate the spectral, far-field and near-field optical properties of metal nanoparticle arrays(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)
Photonic crystal nanocavities are fabricated in silicon membranes covered by thermally annealed silicon-rich nitride films with Erbium-doped silicon nanocrystals. Silicon nitride films were deposited by sputtering on top of silicon on insulator wafers. The nanocavities were carefully designed in order to enhance emission from the nanocrystal sensitized(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)
With soft micro-and nanopatterned materials becoming increasingly useful for various optical, mechanical, electronic, microfluidic, and optofluidic devices, [1–4] the extension of this paradigm to a pure protein-based material substrate would provide entirely new options for such devices. Silk fibroin is an appealing biopolymer for forming such devices(More)
Optical fiber tapers are used to collect photoluminescence emission at ~1.5 µm from photonic crystal cavities fabricated in erbium doped silicon nitride on silicon. In the experiment, photoluminescence collection via one arm of the fiber taper is enhanced 2.5 times relative to free space collection, corresponding to a net collection efficiency of 4%.(More)
Light emission at 1.54 microm from an Er-doped amorphous silicon nitride layer coupled to photonic crystal resonators at cryogenic and room temperatures and under varying optical pump powers has been studied. The results demonstrate that small mode volume, high quality factor resonators enhance Er absorption and emission rates at the cavity resonance. Time(More)
We propose a type of photonic-plasmonic antennas capable of focusing light into subwavelength focal point(s) at several wavelengths, which are formed by embedding conventional dimer gap or bow-tie nanoantennas into multiple-periodic gratings. Fano-type coupling between localized surface plasmon resonances of dimer antennas and photonic modes in the gratings(More)