Search results for "Icon"

Fabrication of DNA origami lattice on silicon surface for DNA-assisted lithography

2022

Metamaterials obtain new properties from having metallized nanoscale features that are often arranged in repeating patterns. In particular, there is a need to create metasurfaces with a negative refractive index. As nanoscale fabrication using conventional top-down methods can be both difficult and time-consuming, bottom-up techniques have gained growing interest. Especially, the DNA origami method can be utilized to assemble lattices with nanoscale features on 2D surfaces, which can then be metallized using DNA-assisted lithography (DALI). This thesis provides a full study of the DNA origami fishnet lattice assembly kinetics and optimization of lattice order on a silicon surface using liqu…

Invited Article: Ultra-broadband terahertz coherent detection via a silicon nitride-based deep sub-wavelength metallic slit

2018

We present a novel class of CMOS-compatible devices aimed to perform the solid-state-biased coherent detection of ultrashort terahertz pulses, i.e., featuring a gap-free bandwidth at least two decades-wide. Such a structure relies on a 1-µm-wide slit aperture located between two parallel aluminum pads, embedded in a 1-µm-thick layer of silicon nitride, and deposited on a quartz substrate. We show that this device can detect ultra-broadband terahertz pulses by employing unprecedented low optical probe energies of only a few tens of nanojoules. This is due to the more than one order of magnitude higher nonlinear coefficient of silicon nitride with respect to silica, the nonlinear material emp…

Phase-Sensitive Detection for Optical Sensing With Porous Silicon

2012

We report on a photonic sensor with an ultralow limit of detection (LoD) based on a phase interrogation readout scheme together with an anisotropic porous silicon (PSi) membrane. First, the fabrication of porous free-standing membranes from medium doped (100) surface oriented silicon, with pore diameters suitable for the infiltration of biomolecules, around 50 nm, is reported. Then, the phase interrogation scheme for characterizing the PSi membranes is presented whose results show that while volumetric sensitivity increases with the membrane thickness, the resolution in the birefringence measurements decrease dramatically due to depolarization effects. The best LoD was found to be equal to …

Electro-optical characterization of new classes of Silicon Carbide UV photodetectors

2014

In this paper, we present the fabrication process steps and the characterization of 4H-SiC vertical Schottky UV detectors, where interdigitated strips, acting as top metal contacts, have been realized in $\hbox{Ni}_{2}\hbox{Si}$ . These devices exploit the pinch-off surface effect. $I$ – $V$ and $C$ – $V$ characteristics, as functions of temperature, were measured in dark conditions. In addition, we have carried out responsivity measurements, for wavelengths ranging from 200 to 400 nm, at varying package temperature and applied reverse bias. A comparison among devices having different strip pitch sizes has been performed, thus finding out that the 10- $\mu\hbox{m}$ pitch class demonstrates …

Il riconoscimento, il lavoro, la cura

2015

Il contributo che propongo vuole essere una riflessione sul tema del riconoscimento, nel contesto lavorativo e nel sociale, che mette l’accento sulle problematiche e sulle difficoltà che le persone incontrano in questo momento storico. Un periodo nel quale non sembrano più avere valore i rapporti di reciprocità e di riconoscimento del proprio percorso formativo e lavorativo, perché altro è divenuto il fulcro d'interesse del mondo del lavoro, ormai da anni indirizzato a coinvolgere le persone nella produttività senza più interessarsi a sufficienza del progetto di vita dei soggetti coinvolti. Si evidenziano i rischi e le sofferenze di soggetti che percepiscono, sempre con maggiore precisione,…

Failure Rate Measurement on Silicon Diodes Reverse Polarized at High Temperature

2017

This paper calculates the failure rate on reversed polarized silicon diodes with the aim to justify, experimentally, the rules of the European Space Agency (ESA) which are referred to the component life’s extension, the reliability increase and the end of life performance enhancement, by using oversized devices (derating rules). In order to verify the derating rules, 80 silicon diodes are used, which are reverse polarized in a high temperature environment. The diodes are divided in 4 groups of 20 diodes, applying a different voltage to each group, in order to relate the failure rate to the applied derating rule. The experiment described in this paper is developed using a temperature acceler…

Terrecotte femminili « con colomba » Diffusione dell’iconografia nel mondo fenicio-punico. Gli esemplari selinuntini del Museo « A. Pepoli » di Trapa…

2014

Text and Illustration in the Medieval Book: Composition, Reading and Reception

2016

Presentaci´´on de este numero: Texto e ilustración en el libro medieval: factura física, lectura y recepción

Semblanza iconográfica de la realeza sapiencial de Alfonso X: las miniaturas liminares de los códices regios

2016

La producción libraria de Alfonso X testimonia la simbiosis perfecta entre las funciones de gobierno y la labor intelectual y sistematiza su ideario político y cultural, no solo en texto, sino también en imagen. A partir de las miniaturas liminares de los códices regios, se evidencia que el motivo icónico privilegiado en la representación personal de Alfonso X es el rey con el libro: se analizan las distintas variantes de este modelo iconográfico que estampa la amplia gama de atribuciones que conforman el concepto de autoría alfonsí y consolida el modelo de la realeza sapiencial castellana.

La "Peregrinació del Venturós Pelegrí" ab les "Cobles de la mort": una sèrie de gravats en setze edicions cerverines (circa 1730-1804)

2015

Resum: Entre el gran nombre d’edicions de la «Peregrinació del Venturós Pelegrí» ab les «Cobles de la mort» impreses a Cervera als segles XVIII-XIX, n’estudiem setze que transmeten la mateixa sèrie de gravats, en la qual es representen algunes escenes del pelegrí visionari i/o l’ànima del purgatori que se li apareix. A banda de reproduir en facsímil tota aquesta sèrie, la portada de quinze edicions i la primera pàgina conservada d’un exemplar únic acèfal, en fem una descripció bibliogràfica i ressenyem els exemplars localitzats en biblioteques d’arreu del món. Tant des del punt de vista quantitatiu com cronològic, aquesta sèrie destaca per ser la més reiterada i documentada entre totes les …