This paper presents a study for the realization of a space mission which employs nanosatellites driven by an external laser source impinging on an optimized lightsail, as a valuable technology to launch swarms of spacecrafts into the Solar System. Nanosatellites propelled by laser can be useful for heliosphere exploration and for planetary observation, if suitably equipped with sensors, or be adopted for the establishment of network systems when placed into specific orbits. By varying the area-to-mass ratio (i.
View Article and Find Full Text PDFThis paper reports on a new strategy for obtaining homogeneous dispersion of grafted quantum dots (QDs) in a photopolymer matrix and their use for the integration of single-photon sources by two-photon polymerization (TPP) with nanoscale precision. The method is based on phase transfer of QDs from organic solvents to an acrylic matrix. The detailed protocol is described, and the corresponding mechanism is investigated and revealed.
View Article and Find Full Text PDFStarch-based films are promising alternatives to synthetic films in food packaging. They were widely studied in terms of mechanical and optical properties. In food packaging, optical properties are of great interest because ultra violet (UV-light) protection is strictly required.
View Article and Find Full Text PDFA novel technique is developed to improve the resolution of two-photon direct laser writing lithography. Thanks to the high collimation enabled by extraordinary ε (near-zero) metamaterial features, ultrathin dielectric hyper-resolute nanostructures are within reach. With respect to the standard direct laser writing approach, a size reduction of 89% and 50%, in height and width respectively, is achieved with the height of the structures adjustable between 5 and 50 nm.
View Article and Find Full Text PDFIn this paper, we present a simple and robust numerical method capable of predicting, with high accuracy, the thermal effects occurring for different gold nanoparticle arrangements under externally applied strain. The physical system is numerically implemented in the COMSOL Multiphysics simulation platform. The photothermal response of different arrangements of gold nanoparticles, resonantly excited by linearly polarized light, is considered with the system at rest and under the action of mechanical stress.
View Article and Find Full Text PDFA simple and robust method able to evaluate and predict, with high accuracy, the optical properties of single and multi-layer nanostructures is presented. The method was implemented using a COMSOL Multiphysics simulation platform and it has been validated by four case studies with increasing numerical complexities: (i) a single thin layer (20 nm) of Ag deposited on a glass substrate; (ii) a metamaterial composed of five bi-layers of Ag/ITO (indium tin oxide), with a thickness of 20 nm each; (iii) a system based on a three-material unit cell (AZO/ITO/Ag), but without any thickness periodicity (AZO stands for AlO/zinc oxide); (iv) an asymmetric nanocavity (thin-ITO/Ag/thick-ITO/Ag). A thorough study of this latter configuration reveals peculiar metamaterial effects that can widen the actual scenario in nanophotonic applications.
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