A5087939708- Carbon Nanotubes in Composites
- Physics of Superconductivity and Magnetism
- Graphene research and applications
- Quantum and electron transport phenomena
- Mechanical and Optical Resonators
- Force Microscopy Techniques and Applications
- Gas Sensing Nanomaterials and Sensors
- Diamond and Carbon-based Materials Research
- Atomic and Subatomic Physics Research
- Metal and Thin Film Mechanics
- Nuclear Physics and Applications
- Cold Atom Physics and Bose-Einstein Condensates
- Semiconductor materials and devices
- ZnO doping and properties
- Particle Detector Development and Performance
- Biofield Effects and Biophysics
- Superconductivity in MgB2 and Alloys
- Advanced Chemical Sensor Technologies
- Superconducting and THz Device Technology
- Radiation Detection and Scintillator Technologies
- Topological Materials and Phenomena
- stochastic dynamics and bifurcation
- Nonlinear Dynamics and Pattern Formation
- Plant and Biological Electrophysiology Studies
- Advanced Thermodynamics and Statistical Mechanics
University of Rome Tor Vergata
2013-2022
Istituto Nazionale di Fisica Nucleare, Roma Tor Vergata
2020-2021
Rome International Center for Materials Science
2019
Diamond Light Source
2019
Istituto Nazionale di Fisica Nucleare, Sezione di Napoli
2019
Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati
2019
University of Trieste
2019
Institute of Structure of Matter
2019
University of Žilina
2008
We investigate experimentally the transport properties of single-walled carbon nanotube bundles as a function temperature and applied current over broad intervals these variables. The analysis is performed on arrays whose axes are aligned along direction externally supplied bias current. data found consistent with charge model governed by tunneling between metallic regions occurring through potential barriers generated nanotube's contact areas or bundle surfaces. Based this experimental...
An atomic force microscopy (AFM) based technique is proposed for the characterization of both indentation modulus and hardness compliant materials. A standard AFM tip used as an indenter to record versus curves analogous those obtained in tests. In order overcome lack information about apex geometry, requires calibration using a set reference samples whose mechanical properties have been previously characterized by means independent technique, such indentation. Due selected samples, has...
We investigate the effect of potassium (K) doping on transport properties aligned single-walled carbon nanotube fibers. The temperature dependence electrical resistance, current-voltage characteristics, and magnetoresistance vs external magnetic field fibers consistently show that enhances metallic character response samples can be quantitatively explained in two thermal regimes separated by a characteristic ${T}^{*}$. At temperatures higher than ${T}^{*}$, data are interpreted framework...
A neutron detection concept is presented that based on superconductive niobium (Nb) strips coated by a boron (B) layer. The working principle of the detector relies nuclear reaction, 10B + n → α 7Li, with and Li ions generating hot spot current-biased Nb strip which in turn induces superconducting-normal state transition. latter recognized as voltage signal evidence incident neutron. above described has been experimentally assessed verified irradiating samples pulsed beam at ISIS spallation...
In this work, the authors investigated MoO3 films with thickness between 30 nm and 1 μm grown at room temperature by solid phase deposition on polycrystalline Cu substrates. Atomic force microscopy, scanning electron tunneling microscopy revealed presence of a homogenous film “grainlike” morphology, while Raman spectroscopy showed an amorphous character film. Nanoindentation measurements evidenced coating hardness stiffness comparable copper substrate ones, Auger spectroscopy, x-ray...
We study the emission of photons from germinating seeds using an experimental technique designed to detect light extremely small intensity. analyze dark count signal without as well photon during germination process. The analysis adopted here, called diffusion entropy (DEA) and originally measure temporal complexity astrophysical, sociological physiological processes, rests on Kolmogorov complexity. updated version DEA used in this paper is determine if generated either by non-ergodic...
An efficient sensing device for NH3 and NOx detection has been realized using ordered arrays of single-walled C nanotubes deposited onto an interdigitated electrode platform operating at room temperature. The material prepared several chemical–physical techniques purification positioning the inside gaps. In particular, both DC AC fields have applied in order to move align nanostructures by electrophoresis dielectrophoresis processes. We investigated effects different voltages a gate contact...
We compare, over wide temperature ranges, the transport properties of single-wall carbon nanotubes arranged in form aligned arrays or fibres. The experimental data show that both forms aggregates present a crossover mechanism from three-dimensional hopping electrons between localized states at high to fluctuation-induced tunnelling across potential barriers low temperature. role junctions formed bundles array and inside fibres is discussed on basis results.
Miniaturized gas-sensing devices that use single-walled carbon nanotubes as active material have been fabricated using two different electrode materials, namely, Au/Cr and NbN. The resistive sensors assembled aligning by dielectrophoresis the nanotube bundles between 40 μ m spaced or NbN multifinger electrodes. sensing tested for detection of H 2 S gas, in concentration range 10–100 ppm, N carrier gas. No resistance changes were detected sensor with electrodes, whereas response electrodes...
We report on microwave emission from linear parallel arrays of underdamped Josephson junctions, which are described by the Frenkel-Kontorova (FK) model. Electromagnetic radiation is detected when biased current singularities (steps) appearing at voltages V(n)=Φ(0)(nc̅/L), where Φ(0)=2.07×10(-15) Wb magnetic flux quantum, and c̅, L, n are, respectively, speed light in transmission line embedding array, L its physical length, an integer. The radiation, fundamental frequency c̅/2L different...
We investigate the transport properties of granular nickel electrodeposited on carbon nanotube fibers by measuring electrical resistance and current voltage characteristics as a function temperature. The bare fiber is governed three-dimensional variable range hopping mechanism, however, semiconducting to metallic transition observed after Ni deposition consequence evolution from weak strong coupling between deposited grains. experimental results indicate that charge in Ni-coated develops...
Optical multimode fibres have a wide variety of applications ranging from industrial to medical use. Therefore, even if they are just used as waveguides or sensors, it is important characterise the whole fingerprint, including optical and mechanical properties such fibres. Since stiffness/elasticity material could influence output fibre due micro-bendings, in this paper we report calculated Young's Modulus acrylate, fluorinated polyimide silicone, which four most coating materials for...
A hybrid chemical vapor deposition (CVD)‐powder flowing technique specifically developed in lab has been employed to produce high‐quality polycrystalline diamond layers containing Ti inclusions. Morphology, structural features, and surface composition of nanocomposite diamond‐based samples produced by different growth times have analyzed scanning electron microscopy, Raman Auger spectroscopy, respectively. The CVD methodology adopted for the incorporation lattice does not perturb crystalline...
Diamond-like carbon (DLC) films were deposited using two different types of high current arc evaporation. The first process used a magnetic particle filter to remove droplets from the plasma. For second process, samples put into metallic cage which was placed directly above plasma source. both processes, we varied substrate temperature 21 350 °C in order investigate effect. characterized SEM, AFM, XPS, Raman Spectroscopy, Ellipsometry, Photometry, and Nano Indentation compare methods...
Abstract We report on phenomena observed in planar integrated networks obtained connecting superconducting island by Josephson tunnel junctions. These networks, identifiable as tree-like graphs, have branches consisting of series arrays junctions which can be individually current biased and characterized. Both supercurrents gap parameters the embedded graph structures display properties significantly different from those “reference” fabricated same chips having identical geometrical shape....
The structural and electronic properties of the methylammonium lead iodide (MAPbI3, MA = CH3NH3) perovskite are investigated as a function temperature by transport measurements, in situ x-ray diffraction, optical emission. Lowering temperature, transition from tetragonal to orthorhombic phase takes place, around 160 K. Such transition, monitored temperature-dependent diffraction emission, is followed an inversion dependence electrical resistivity semiconductor-like metal-like one. for such...