Ricerc@Sapienza

Nafion membranes, are polymeric thin films widely employed in micro-batteries and fuel cells. These devices are expected to play a key role in the next generation energy systems for use in vehicles as a replacement to combustion engines. In fact, a minimum environmental impact is guaranteed by reduced carbon dioxide emissions. It is usually complicated to investigate the behavior of thin membranes through experiments. Therefore, numerical simulations are carried out in order to enable a better understanding of the phenomena and of the multi-field couplings occurring in polymeric membranes.

A biosensor platform based on Bloch Surface Waves and operating in angular interrogation mode is applied to the detection of a clinical biomarker (HER2-neu/ERBB2) related to breast cancer initiation/progression. Preparing regions for specific recognition of different proteins as well as a reference on the biochip enables to correct the signal for nonspecific effects. Additionally, label-free analysis and surface wave enhanced fluorescence detection can be applied and compared directly on the platform. Cell lysates with high and low expression levels of ERBB2 are analyzed.

We report on the detection of an angiogenic molecule Vascular Endothelial Growth Factor (VEGF) in different biological matrices by means of a new integrated biosensing platform exploiting the properties of Bloch surface waves. The new platform takes advantage of a tandem configuration, in which both label-free and enhanced fluorescence detection are implemented. Specifically designed one dimensional photonic crystals were deposited directly on disposable and low cost plastic biochips.

Photothermal and photoacoustic techniques are utilized to explore the thermal properties of metal based metasurfaces. We experimentally evidence the role of the symmetry in the heat transport and its relation with the optical circular dichroism.

This paper shows a detailed analysis of the semiconductor-to-metal transition (SMT) in a vanadium dioxide (VO2) film deposited on silicon wafer. The vanadium dioxide phase transition is studied in the wide mid-infrared range 2-12 μm, by analyzing the transmittance and the reflectance measurements, and the calculated emissivity from the sample. The temperature behavior of the emissivity during the SMT put into evidence the phenomenon of the anomalous absorption in vanadium dioxide which has been explained by applying the Maxwell Garnett effective medium approximation theory.

We investigated a metamaterial composed by silicon carbide (SiC) subwavelength oriented wires, onto silicon substrate in the mid- to long- infrared range. A simple but versatile method was developed and implemented, combining homogenization techniques with the transfer matrix method for birefringent layered materials to model an effective medium layer where different inclusions content (filling factor) as well as different shape and orientation of inclusions (depolarization factors) are taken into account.

This paper studies the IR properties of a VO2-based multilayer structure with an emittance that increase with the temperature. A good tunability of the emissivity in long-wave infrared spectral region (8–12 µm) has been detected, with a positive emissivity differential of about 0.2. The transition of the long wave emissivity ε with the temperature is fully reversible according to a hysteresis cycle, with a transition temperature of 67 °C and a thermal bandwidth of only 8 °C. The multilayer structure also shows two emission peaks both in the heating cycle and in the cooling cycle.

In this study, the measured wave data for year 2010 at 3 hour time step for six sites in the Caspian sea, Persian Gulf and Oman Sea of Iran have been statistically analysed to determine the wave power potential of Iranian coastlines. The statistical attitudes allows to estimate the significant weight height (Hs), peak wave energy period (Tp), and the wave energy flux for unit of crest length.

Remnant radiation from the early universe, known as the Cosmic Microwave Background (CMB), has been redshifted and cooled, and today has a blackbody spectrum peaking at millimetre wavelengths. The QUBIC (Q&U Bolometric Interferometer for Cosmology) instrument is designed to map the very faint polaristion structure in the CMB. QUBIC is based on the novel concept of bolometric interferometry in conjunction with synthetic imaging. It will have a large array of input feedhorns, which creates a large number of interferometric baselines.

Gold nanoparticles with an average diameter of 10 nm, functionalized by the dye molecule rhodamine B isothiocyanate, have been synthesized. The resulting material has been extensively characterized both chemically, to investigate the bonding between the dye molecules and the nanoparticles, and physically, to understand the details of the aggregation induced by interaction between dye molecules on different nanoparticles.