Andrea Chiappini

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In the paper the analysis of luminescence emission in the VIS spectra range of fabricated multicomponent glasses doped with rare-earth ions and PMMA doped with dyes were presented. Up-conversion emission in: germanate glass co-doped with 0.5Yb<sub>2</sub>O<sub>3</sub>/0.75Eu<sub>2</sub>O<sub>3</sub> mol% under 976 nm excitation has been investigated.(More)
Er<sup>3&#x002B;</sup>-acticated silica-hafnia glass-ceramic waveguides were fabricated by bottom-up and top-down approaches. The pros and cons of the procedures in terms of optical, spectroscopic and structural properties are reported, in particular regarding attenuation coefficient, NIR emission, and local environment for the rare-earth ions. The results(More)
Transparent glass-ceramics, activated by luminescent species, present an important class of photonic materials because their specific optical, spectroscopic and structural properties. Several top-down and bottom-up techniques have been developed for transparent glass ceramic fabrication. Among them, laser material processing plays an important role and many(More)
In this paper, we present a short review of the activity performed in developing glass-based photonic structures on the nano and micro scale, based on the sol-gel techniques and activated by rare earth ions. Optical and spectroscopic assessment of glass ceramic waveguides is discussed. Luminescence enhancement is demonstrated. Refractive index modulation(More)
This paper presents optical and spectroscopic assessment, as well as morphological and structural characterization of nanoscaled photonic structures: (i) rare earth-activated oxide and fluoride glass ceramics planar waveguides; (ii) Er<sup>3+</sup>-activated micro-nano silica spheres and core-shell-like structures; (iii) rf sputtering-fabricated planar(More)
We discuss the possible use of photonic crystals as strain sensors. We demonstrate the feasible fabrication of a crystal having sub-micrometric polystyrene colloidal spheres in a PDMS matrix on a rubber substrate, and we demonstrate that the photonic properties change with substrate elongation according to theoretical prediction. The crystal's sensitivity(More)
Diamond is a promising platform for sensing and quantum processing owing to the remarkable properties of the nitrogen-vacancy (NV) impurity. The electrons of the NV center, largely localized at the vacancy site, combine to form a spin triplet, which can be polarized with 532 nm laser light, even at room temperature. The NV's states are isolated from(More)
Glass-ceramics are nanocomposite materials which offer specific characteristics of capital importance in photonics. This kind of two-phase materials is constituted by nanocrystals embedded in a glass matrix and the respective composition and volume fractions of crystalline and amorphous phase determine the properties of the glass-ceramic. Among these(More)
We present some results regarding the coating of spherical microresonators and their different applications in photonics. The spherical microresonators high Q-factor and low mode volume make them perfect for a number of photonics applications. A thin film coating on the surface of the resonator using an optically active or passive layer can be used to(More)
Fabrication of confined structures, where light can be confined over nano or micro scale region is fantastic challenge for nano-science based technologies. Manufacture of such structures has become possible due to the opportunity delivered by nanotechnology, which opens the way to the study of new functional artificial materials and plasmonic structures,(More)