Luca Mezi - Academia.edu (original) (raw)

Papers by Luca Mezi

Machines

We present the electrical and optical design, assembling, and thorough experimental characterizat... more We present the electrical and optical design, assembling, and thorough experimental characterization of two compact arrays of short-wavelength ultraviolet (UV-C) light-emitting diodes (LEDs) suitable for near-field irradiation. Through a combination of technical expedients, we have achieved effective thermal management such that long-lasting irradiations are possible without appreciable deterioration of UV-C emission. We successfully used these compact UV-C LED arrays for long lasting irradiation tests aimed at generating the biosynthesis of defensive metabolites that enhance the resistance of plants and fruits to pathogen attacks. Finally, we comment on the possibility of implementing these compact UV-C sources on robotic systems to make an automated device suitable to reduce pesticide use in agricultural crops.

La bussola solare brevettata da ENEA si caratterizza per la capacita di misurare la direzione del... more La bussola solare brevettata da ENEA si caratterizza per la capacita di misurare la direzione del Nord geografico con un livello di accuratezza di 0.01 gradi, nettamente migliore rispetto a quello delle migliori bussole magnetiche ed elettroniche sinora realizzate. Ovviamente, la bussola ENEA e stata progettata per poter funzionare in condizioni di Sole pieno, ma cosa accade quando il disco solare e parzialmente oscurato, ad esempio da una nuvola? Per rispondere accuratamente a questa domanda abbiamo misurato le prestazioni della bussola solare ENEA prima, durante e dopo l’eclisse parziale di Sole del 20 Marzo 2015. I risultati delle misure, riassunti in questo rapporto tecnico, dimostrano che quando il disco solare e coperto per una frazione pari al 35%, in modo asimmetrico, la bussola presenta uno scostamento di circa 0.08 gradi (pari a circa 5’) rispetto alla misura con disco solare pieno. Questo valore resta ancora migliore rispetto agli errori introdotti dalle bussole magnetich...

2015 40th International Conference on Infrared, Millimeter, and Terahertz waves (IRMMW-THz), 2015

The conceptual design study of a high-power high-frequency Cyclotron Auto-Resonance Maser (CARM) ... more The conceptual design study of a high-power high-frequency Cyclotron Auto-Resonance Maser (CARM) has been undertaken at the ENEA-Frascati research center in 2013. CARMs could be effective mm-wave sources for electron cyclotron waves and plasma diagnostics in magnetic confinement fusion reactors. The project is advancing quickly with the technical design of some major parts now completed and ready to enter the realization phase. Subsystems under conceptual or detailed design are presented together with the outlook of next steps.

Plasma Sources Science and Technology, 2001

The high-current (up to 40 kA) fast electrical discharge Z-pinch in an argon-filled capillary has... more The high-current (up to 40 kA) fast electrical discharge Z-pinch in an argon-filled capillary has been developed to produce pulses of intense soft x-ray radiation in the spectral region of 2-50 nm. We present results of an experimental analysis of plasma evolution in the Z-pinch and discuss them in comparison with a theoretical model. The effects of the electrical circuit

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2005

We discuss a phenomenological model, capable of reproducing the effect of potential well distorti... more We discuss a phenomenological model, capable of reproducing the effect of potential well distortion and of saw-tooth instability on an e-beam propagating in a storage ring. We study the same effect when the Free Electron Dynamics is included.

The behavior of a FEL operating in the pulsed saturated regime, is reproduced by the FEL integral... more The behavior of a FEL operating in the pulsed saturated regime, is reproduced by the FEL integral equation, suitably modified to include non-linear effects. The method allows to evaluate the FEL dynamics by means of a relatively negligible computer time. The relevant predictions are compared with available experimental and numerical data.

Physical Review Letters, 2001

The stabilization of nonlinear excitations by noise is a topic of fundamental importance in many ... more The stabilization of nonlinear excitations by noise is a topic of fundamental importance in many physical problems. We discuss a genuine example within the context of storage ring-free electron laser physics, by presenting a model which allows the characterization of the system evolution and the determination of the conditions leading to the suppression of instabilities of sawtooth type. The conclusions of the model are confirmed by a comparison with experimental results on the Super Aco Storage Ring-Free Electron Laser.

La bussola solare elettronica brevettata da ENEA è uno strumento compatto, automatico, accurato (... more La bussola solare elettronica brevettata da ENEA è uno strumento compatto, automatico, accurato (risoluzione migliore di un primo d’arco, pari a 0,016 gradi) e veloce (fornisce l’orientamento in pochi secondi). La bussola ENEA è stata già usata con successo per rilevamenti di orientamento in Antartide (in collaborazione con INGV), per il controllo della movimentazione e dell’orientamento dell’asse di rotazione degli specchi delle centrali solari a concentrazione (in collaborazione con D.D. s.r.l.), e per la progettazione di meridiane. In questo rapporto presentiamo l’uso della bussola ENEA nelle misure di orientamento di alcune strutture della Grotta di Tiberio adiacente alla Villa appartenuta nel I secolo d.C. all'imperatore romano Tiberio, presso l’area annessa al Museo Archeologico Nazionale di Sperlonga, in provincia di Latina. Le misure di orientamento sono finalizzate a verificare se tali strutture presentino una direzione privilegiata rispetto a particolari eventi astronomici, collegati al moto apparente del Sole. The Electronic solar compass, patented by ENEA, is compact, automatic, accurate (the orientation/azimuth is determined with a resolution better than 0.016°), and fast (it provides the orientation in few seconds). The ENEA compass has been successfully used for orientation measurements in Antarctica (in collaboration with INGV), for handling the movement and checking the rotation axis orientation of the mirrors in the concentrated solar power plants (in collaboration with D.D. srl,), and for the design of sundials. In this report, we exploit the ENEA solar compass in archeoastronomy, specifically in orientation measurements of some structures at the Grotta di Tiberio, a cave adjacent to the Villa of the emperor Tiberius (1st century AD) located in the archaeological site nearby the National Archaeological Museum of Sperlonga, in the province of Latina. The measures are aimed at verifying whether these structures provide references to particular astronomical events, connected to the apparent motion of the Sun.

Applied Optics, 2022

We have developed an app, named Sunpass, that is able to convert every smartphone into a solar co... more We have developed an app, named Sunpass, that is able to convert every smartphone into a solar compass. Sunpass uses input data from the smartphone sensors, calculates the Sun position, and elaborates data to give the desired information. The azimuth values measured by a smartphone equipped with Sunpass show a typical accuracy of 0.5°, which is limited by camera aberrations and misalignment of both accelerometer and CCD camera of the smartphone. In this paper, we show that both accuracy and reliability in azimuth measurements can be improved by a specific calibration procedure and a dedicated mechanical tool. We obtained a remarkable accuracy better than 0.06° on the single azimuth measurements, which improves to 0.03° on the average of eight measurements.

Journal of Instrumentation, 2019

This contribution to ECPD2019 is dedicated to the memory of Anatoly Faenov. During a period of ap... more This contribution to ECPD2019 is dedicated to the memory of Anatoly Faenov. During a period of approximately thirteen years 1994–2006, Anatoly and his wife Tatiana Pikuz (simply “Tania” for friends), accepting the frequent invitations of the National Institute for Nuclear Physics (INFN) and of the Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), cooperated with many Italian research laboratories dedicated to EUV and soft X-ray generation, spread in different towns (L'Aquila, Frascati, Milano, Padova, Pisa, Roma, etc.). In spite of the fact that they could stay in Italy only about one or two months per year, their activity was so intense that more than 50 peer- reviewed publications were generated from their experimental and theoretical work (just considering only the results obtained at L'Aquila and Tor Vergata—Rome Universities and at the ENEA Research Center of Frascati), without mentioning the cultural atmosphere that they ...

18th Italian National Conference on Photonic Technologies (Fotonica 2016), 2016

After a brief description of the extreme ultraviolet (EUV) radiation peculiarities, the main char... more After a brief description of the extreme ultraviolet (EUV) radiation peculiarities, the main characteristics of the ENEA Discharge Produced Plasma (DPP) EUV source are described. An efficient debris mitigation system has been developed and tested on the DPP source, to protect delicate objects from plasma emitted debris bombardment. The DPP source has been successfully utilized for pattern generation by EUV irradiation of photonic materials like lithium fluoride crystals and various innovative photoresists. A simple contact EUV lithography technique has been demonstrated to be effective for sub-micrometric resolution patterning on the above mentioned materials. Examples of obtained patterns are presented and discussed.

AIP Conference Proceedings, 2002

In this paper, we report on the realization of a capillary discharge soft x-ray laser operating a... more In this paper, we report on the realization of a capillary discharge soft x-ray laser operating at 46.9 nm pumped by a 30 kA peak value, 150 ns half cycle duration current pulse (corresponding to a mean current slope of about 5 1011 A/s). The slope of the pumping current is sufficiently high to produce the plasma compression and laser

High Power Laser Science and Engineering, 2015

A discharge-produced-plasma (DPP) source emitting in the extreme ultraviolet (EUV) spectral regio... more A discharge-produced-plasma (DPP) source emitting in the extreme ultraviolet (EUV) spectral region is running at the ENEA Frascati Research Centre. The plasma is generated in low-pressure xenon gas and efficiently emits 100-ns duration radiation pulses in the 10–20-nm wavelength range, with an energy of$20~\text{mJ}/\text{shot}/\text{sr}$at a 10-Hz repetition rate. The complex discharge evolution is constantly examined and controlled with electrical measurements, while a ns-gated CCD camera allowed observation of the discharge development in the visible, detection of time-resolved plasma-column pinching, and optimization of the pre-ionization timing. Accurately calibrated Zr-filtered PIN diodes are used to monitor the temporal behaviour and energy emission of the EUV pulses, while the calibration of a dosimetric film allows quantitative imaging of the emitted radiation. This comprehensive plasma diagnostics has demonstrated its effectiveness in suitably adjusting the source configur...

We describe the technique and apparatus to write invisible patterns on thin tags of alkali halide... more We describe the technique and apparatus to write invisible patterns on thin tags of alkali halides by using an extreme ultraviolet radiation source. We have experimentally demonstrated that lithium fluoride thin-films tags written using this method are almost impossible to counterfeit, and offer a much better protection than the available anti-counterfeiting techniques. The results of preliminary tests of exposure to γ-, x-and β-radiation emitted by several radio-nuclides, like Co-60, Cs-137, Na-22, and Ba-133 are promising for the use of these tags to track radioactive materials, in order to fight phenomena impacting security, like the illicit disposal and traffic in radioactive waste. Il presente articolo descrive la tecnica e gli strumenti per scrivere disegni invisibili su sottili etichette di metalli alcalini terrosi utilizzando una fonte di radiazione nell'estremo ultravioletto. È stato dimostrato sperimentalmente che il nostro metodo di scrittura rende praticamente imposs...

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2013

ABSTRACT Schwarzschild objectives are widely used in the extreme ultraviolet (EUV)/soft X-ray spe... more ABSTRACT Schwarzschild objectives are widely used in the extreme ultraviolet (EUV)/soft X-ray spectral region both as reduction and magnification optics, e.g. for small-field projection lithography and microscopy, respectively. When using a Schwarzschild objective as a micro-exposure tool (MET) at high spatial resolution (half-pitch≤0.1 μm), in addition to the tight requirements on the design and surface figure for the single optics, also an accurate alignment between the two mirrors is needed to reach the planned spatial imaging detail. Ideally, at-wavelength alignment should be done in order to overcome limitations due to diffractive effects. While this can be easily performed on synchrotron beam lines, it becomes time expensive (and components consuming) on low-power laboratory plasma sources. In this work we propose and test a new technique to align a EUV Schwarzschild objective by means of ultraviolet light. The aligned objective allowed the attainment of lithographic patterning with edge response of 90 nm, as part of the laboratory-scale MET for EUV projection lithography realized at the ENEA Frascati Research Centre.

Short Wavelength Laboratory Sources, 2014

Laser produced plasmas are widely used as extreme ultraviolet (EUV) and soft X-ray radiation sour... more Laser produced plasmas are widely used as extreme ultraviolet (EUV) and soft X-ray radiation sources in many different fields. Lithography is one of the most challenging applications of the EUV spectral region (5-50 nm). The worldwide importance of EUV lithography (EUVL) is basically due to its potential to extend optical projection lithography to higher resolution in integrated circuit manufacturing, thanks to the shorter wavelength and to the availability of high reflectivity normal incidence mirrors. In addition to the huge technological and financial effort carried out by international consortia to raise EUVL at the industrial level, less expensive laboratory-scale facilities have been built up to perform component testing and metrology. Within a national project on nanotechnologies at the ENEA Research Centre in Frascati a micro exposure tool (MET) has been designed and developed for projection lithography, exploiting the facility EGERIA (extreme ultraviolet radiation generation for experimental research and industrial applications). EGERIA is a EUV/soft X-ray laser produced plasma source equipped with a high efficiency debris mitigation system (DMS).

Applications of X Rays Generated from Lasers and Other Bright Sources II, 2001

We report on a fast soft x-ray source consisting in a high temperature small diameter plasma colu... more We report on a fast soft x-ray source consisting in a high temperature small diameter plasma column produced by electric discharge in a ceramic capillary. This source was developed to produce pulses of few hundred nanosecond duration for EUV lithography, x-ray ...

SPIE Proceedings, 2004

A new imaging detector for EUV or soft-X-ray radiation based on optically stimulated luminescence... more A new imaging detector for EUV or soft-X-ray radiation based on optically stimulated luminescence (OSL) of lithium fluoride (LiF) films or crystals is presented. The first micro-radiography images of biological samples and of meshes obtained on LiF using a laser-plasma source or an ...

Optics & Laser Technology, 1994

The influence of the current return geometry on the electric field uniformity in the discharge la... more The influence of the current return geometry on the electric field uniformity in the discharge laser chamber is studied, and a suggestion for better electrode profiles, giving lower electric field spatial gradients, is proposed.

Machines

2015 40th International Conference on Infrared, Millimeter, and Terahertz waves (IRMMW-THz), 2015

Plasma Sources Science and Technology, 2001

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2005

Physical Review Letters, 2001

Applied Optics, 2022

Journal of Instrumentation, 2019

18th Italian National Conference on Photonic Technologies (Fotonica 2016), 2016

AIP Conference Proceedings, 2002

High Power Laser Science and Engineering, 2015

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2013

Short Wavelength Laboratory Sources, 2014

Applications of X Rays Generated from Lasers and Other Bright Sources II, 2001

SPIE Proceedings, 2004

Optics & Laser Technology, 1994

Applied Optics , 2022

We have developed an app, named Sunpass, able to convert every smartphone into a solar compass. S... more We have developed an app, named Sunpass, able to convert every smartphone into a solar compass. Sunpass uses input data from the smartphone sensors, calculates the Sun position, and elaborates data to give the desired information.
The azimuth values measured by a smartphone equipped with Sunpass show a typical accuracy of 0.5°, which is limited by camera aberrations and misalignment of both accelerometer and CCD camera of the smartphone.
In this paper, we show that both accuracy and reliability in azimuth measurements can be improved by a specific calibration procedure and a dedicated mechanical tool. We obtained a remarkable accuracy better than 0.06° on the single azimuth measurements, which improves to 0.03° on the average of eight measurements.