23 research outputs found
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IKNO, a user facility for coherent terahertz and UV synchrotron radiation
IKNO (Innovation and KNOwledge) is a proposal for a multi-user facility based
on an electron storage ring optimized for the generation of coherent
synchrotron radiation (CSR) in the terahertz frequency range, and of broadband
incoherent synchrotron radiation ranging from the IR to the VUV. IKNO can
be operated in an ultra-stable CSR mode with photon flux in the terahertz
frequency region up to nine orders of magnitude higher than in existing thirdgeneration
light sources. Simultaneously to the CSR operation, broadband
incoherent synchrotron radiation up to VUV frequencies is available at the
beamline ports. The main characteristics of the IKNO storage and its
performance in terms of CSR and incoherent synchrotron radiation are
described in this paper. The proposed location for the infrastructure facility is
Sardinia, Italy
A Novel Particle/Photon Detector Based on a Superconducting Proximity Array of Nanodots
The current frontiers in the investigation of high-energy particles demand for new detection methods. Higher sensitivity to low-energy deposition, high-energy resolution to identify events and improve the background rejection, and large detector masses have to be developed to detect even an individual particle that weakly interacts with ordinary matter. Here, we will describe the concept and the layout of a novel superconducting proximity array which show dynamic vortex Mott insulator to metal transitions, as an ultra-sensitive compact radiation-particle detector
Potassium-Doped Para-Terphenyl: Structure, Electrical Transport Properties and Possible Signatures of a Superconducting Transition
Preliminary evidence for the occurrence of high-TC superconductivity in alkali-doped organic materials, such as potassium-doped p-terphenyl (KPT), were recently obtained by magnetic susceptibility measurements and by the opening of a large superconducting gap as measured by ARPES and STM techniques. In this work, KPT samples have been synthesized by a chemical method and characterized by low-temperature Raman scattering and resistivity measurements. Here, we report the occurrence of a resistivity drop of more than 4 orders of magnitude at low temperatures in KPT samples in the form of compressed powder. This fact was interpreted as a possible sign of a broad superconducting transition taking place below âŒ90 K in granular KPT. The granular nature of the KPT system appears to be also related to the âŒ20 K broadening of the resistivity drop around the critical temperature
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Proximity array device: a novel photon detector working in long wavelengths
We present here an innovative photon detector based on the proximity junction array device (PAD) working at long wavelengths. We show that the vortex dynamics in PAD undergoes a transition from a Mott insulator to a vortex metal state by application of an external magnetic field. The PAD also evidences a Josephson I-V characteristic with the external field dependent tunneling current. At high applied currents, we observe a dissipative regime in which the vortex dynamics is dominated by the quasi-particle contribution from the normal metal. The PAD has a relatively high photo-response even at frequencies below the expected characteristic frequency while, its superconducting properties such as the order parameter and the Josephson characteristic frequency can be modulated via external fields to widen the detection band. This device represents a promising and reliable candidate for new high-sensitivity long-wavelength detectors. © 2020 by the authors. Licensee MDPI, Basel, Switzerland
MoO3 films grown on polycrystalline Cu: Morphological, structural, and electronic properties
In this work, the authors investigated MoO3 films with thickness between 30 nm and 1 Όm grown at room temperature by solid phase deposition on polycrystalline Cu substrates. Atomic force microscopy, scanning electron microscopy, and scanning tunneling microscopy revealed the presence of a homogenous MoO3 film with a "grainlike" morphology, while Raman spectroscopy showed an amorphous character of the film. Nanoindentation measurements evidenced a coating hardness and stiffness comparable with the copper substrate ones, while Auger electron spectroscopy, x-ray absorption spectroscopy, and secondary electron spectroscopy displayed a pure MoO3 stoichiometry and a work function Ί MoO3 = 6.5 eV, 1.8 eV higher than that of the Cu substrate. MoO3 films of thickness between 30 and 300 nm evidenced a metallic behavior, whereas for higher thickness, the resistance-temperature curves showed a semiconducting character
The potential of eupraxia@sparc_lab for radiation based techniques
A proposal for building a Free Electron Laser, EuPRAXIA@SPARC_LAB, at the Laboratori Nazionali di Frascati, is at present under consideration. This FEL facility will provide a unique combination of a high brightness GeV-range electron beam generated in a X-band RF linac, a 0.5 PW-class laser system and the first FEL source driven by a plasma accelerator. The FEL will produce ultra-bright pulses, with up to 1012 photons/pulse, femtosecond timescale and wavelength down to 3 nm, which lies in the so called âwater windowâ. The experimental activity will be focused on the realization of a plasma driven short wavelength FEL able to provide high-quality photons for a user beamline. In this paper, we describe the main classes of experiments that will be performed at the facility, including coherent diffraction imaging, soft X-ray absorption spectroscopy, Raman spectroscopy, Resonant Inelastic X-ray Scattering and photofragmentation measurements. These techniques will allow studying a variety of samples, both biological and inorganic, providing information about their structure and dynamical behavior. In this context, the possibility of inducing changes in samples via pump pulses leading to the stimulation of chemical reactions or the generation of coherent excitations would tremendously benefit from pulses in the soft X-ray region. High power synchronized optical lasers and a TeraHertz radiation source will indeed be made available for THz and pumpâprobe experiments and a split-and-delay station will allow performing XUV-XUV pumpâprobe experiments.Fil: Balerna, Antonella. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Bartocci, Samanta. UniversitĂ degli studi di Sassari; ItaliaFil: Batignani, Giovanni. UniversitĂ degli studi di Roma "La Sapienza"; ItaliaFil: Cianchi, Alessandro. Universita Tor Vergata; Italia. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Chiadroni, Enrica. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Coreno, Marcello. Istituto Nazionale Di Fisica Nucleare.; Italia. Istituto di Struttura della Materia; ItaliaFil: Cricenti, Antonio. Istituto di Struttura della Materia; ItaliaFil: Dabagov, Sultan. Istituto Nazionale Di Fisica Nucleare.; Italia. National Research Nuclear University; Rusia. Lebedev Physical Institute; RusiaFil: Di Cicco, Andrea. Universita Degli Di Camerino; ItaliaFil: Faiferri, Massimo. UniversitĂ degli studi di Sassari; ItaliaFil: Ferrante, Carino. UniversitĂ degli studi di Roma âLa Sapienzaâ; Italia. Center for Life Nano Science @Sapienza; ItaliaFil: Ferrario, Massimo. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Fumero, Giuseppe. UniversitĂ degli studi di Roma âLa Sapienzaâ; ItaliaFil: Giannessi, Luca. Elettra-Sincrotrone Trieste; Italia. ENEA C.R. Frascati; ItaliaFil: Gunnella, Roberto. Universita Degli Di Camerino; ItaliaFil: Leani, Juan Jose. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de FĂsica Enrique Gaviola. Universidad Nacional de CĂłrdoba. Instituto de FĂsica Enrique Gaviola; ArgentinaFil: Lupi, Stefano. UniversitĂ degli studi di Roma âLa Sapienzaâ; Italia. Istituto Nazionale di Fisica Nucleare (INFN) Sezione di Roma La Sapienza; ItaliaFil: Macis, Salvatore. UniversitĂ degli Studi di Roma Tor Vergata; Italia. Istituto Nazionale di Fisica Nucleare (INFN) Sezione di Roma Tor Vergata; ItaliaFil: Manca, Rosa. UniversitĂ degli studi di Sassari; ItaliaFil: Marcelli, Augusto. Istituto Nazionale Di Fisica Nucleare.; Italia. Consiglio Nazionale delle Ricerche; ItaliaFil: Masciovecchio, Claudio. Elettra-Sincrotrone Trieste; ItaliaFil: Minicucci, Marco. Universita Degli Di Camerino; ItaliaFil: Morante, Silvia. Universita Tor Vergata; Italia. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Perfetto, Enrico. Universita Tor Vergata; Italia. Consiglio Nazionale delle Ricerche; ItaliaFil: Petrarca, Massimo. UniversitĂ degli studi di Roma "La Sapienza"; Italia. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Pusceddu, Fabrizio. UniversitĂ degli studi di Sassari; ItaliaFil: Rezvani, Javad. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Robledo, JosĂ© Ignacio. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de FĂsica Enrique Gaviola. Universidad Nacional de CĂłrdoba. Instituto de FĂsica Enrique Gaviola; ArgentinaFil: Rossi, Giancarlo. Centro FermiâMuseo Storico della Fisica e Centro Studi e Ricerche âEnrico Fermiâ; Italia. Istituto Nazionale Di Fisica Nucleare.; Italia. Universita Tor Vergata; ItaliaFil: Sanchez, Hector Jorge. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto de FĂsica Enrique Gaviola. Universidad Nacional de CĂłrdoba. Instituto de FĂsica Enrique Gaviola; ArgentinaFil: Scopigno, Tullio. Center for Life Nano Science @Sapienza; Italia. UniversitĂ degli studi di Roma "La Sapienza"; ItaliaFil: Stefanucci, Gianluca. Universita Tor Vergata; Italia. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Stellato, Francesco. Universita Tor Vergata; Italia. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Trapananti, Angela. Universita Degli Di Camerino; ItaliaFil: Villa, Fabio. Istituto Nazionale Di Fisica Nucleare.; Itali
Lunar Gravitational-Wave Antenna
Monitoring of vibrational eigenmodes of an elastic body excited by
gravitational waves was one of the first concepts proposed for the detection of
gravitational waves. At laboratory scale, these experiments became known as
resonant-bar detectors first developed by Joseph Weber in the 1960s. Due to the
dimensions of these bars, the targeted signal frequencies were in the kHz
range. Weber also pointed out that monitoring of vibrations of Earth or Moon
could reveal gravitational waves in the mHz band. His Lunar Surface Gravimeter
experiment deployed on the Moon by the Apollo 17 crew had a technical failure
rendering the data useless. In this article, we revisit the idea and propose a
Lunar Gravitational-Wave Antenna (LGWA). We find that LGWA could become an
important partner observatory for joint observations with the space-borne,
laser-interferometric detector LISA, and at the same time contribute an
independent science case due to LGWA's unique features. Technical challenges
need to be overcome for the deployment of the experiment, and development of
inertial vibration sensor technology lays out a future path for this exciting
detector concept.Comment: 29 pages, 17 figure
Investigations of time-dependent chemical-physical phenomena with THz spectroscopy
We may investigate time-dependent phenomena in a non pump-probe configuration combining a SR THz source and an IR thermal source. A âproof of conceptsâ experiment of the evaporation of a deuterated water droplet cast on a diamond substrate was performed simultaneously in the IR and in the THz ranges
Water evaporation studied by <i>in situ</i> time-resolved infrared spectroscopy
Evaporation of water is a fundamental and ubiquitous process that is on the ground of different types of nanoscience phenomena such as evaporation induced self-assembly. Even if water evaporation is a very basic phenomenon, there is still a lack of experiments that give a direct insight of the process. In situ application of rapid scan time-resolved infrared spectroscopy to an evaporating droplet has allowed monitoring the process at different relative humidity conditions. The experiments have been performed in the near-infrared range using water and deuterated water. The water evaporation appears as a continuous process that is not affected by changes of relative humidity in the external environment. This result, however, is affected by the impossibility to discriminate the contribution of the adsorbed water. The same experiment repeated with a deuterated water droplet has allowed, instead, a direct observation of the contribution during the evaporation process from water in the external environment. The time-resolved analysis has shown that at higher relative humidity the water adsorption is enhanced and that this process is time delayed with respect to the beginning of the evaporation process
Time resolved IR and X-ray simultaneous spectroscopy: new opportunities for the analysis of fast chemical-physical phenomena in materials
New powerful sources and advanced analytical techniques have been considered in the last decade to face up the continuously increasing scientific demands, in particular, in materials science. As an example, nano- science and nanotechnology researches are characterized by ultimate spatial resolution, fast and ultrafast time- -resolved analysis, but the complexity of the investigated phenomena requires new analytical capabilities and new experimental techniques were introduced in the research arena. The availability all over the world of brilliant synchrotron radiation sources offers incredible opportunities. Many challenging experiments were made possible by these sources and understanding of many complex dynamical problems was obtained. Nevertheless, a strong demand of new analytical approaches, mainly based on concurrent and possibly simultaneous time-resolved experimental techniques, is emerging. Pioneering time resolved experiments combining X-ray and infrared radiation with a conventional source were performed more than a decade ago. Nowadays, many beamlines at third generation synchrotron radiation facilities are equipped with conventional sources to allow complementary techniques and the strategy of a concurrent analysis is mandatory in the investigation of many phenomena in frontier multidisciplinary researches. Moreover, new opportunities will be available by means of concurrent spectroscopic experiments investigating complex phenomena on a short timescale, from the sub-second to the microsecond time domain. We will present and discuss researches where the combination of IR and X-ray simultaneous experiments may return unique information on complex dynamical processes and phase transitions occurring in materials science. Finally, we will briefly describe the conceptual layout of a synchrotron radiation beamline to perform concurrent IR and X-ray experiments