1. New achievements in orbital angular momentum beam characterization using a Hartmann wavefront sensor and the Kirkpatrick-Baez active optical system KAOSLuka Novinec, Matteo Pancaldi, Flavio Capotondi, Giovanni De Ninno, Francesco Guzzi, George Kourousias, Emanuele Pedersoli, Barbara Ressel, Benedikt Rösner, Alberto Simoncig, 2024, original scientific article Abstract: Advances in physics have been significantly driven by state-of-the-art technology, and in photonics and X-ray science this calls for the ability to manipulate the characteristics of optical beams. Orbital angular momentum (OAM) beams hold substantial promise in various domains such as ultra-high-capacity optical communication, rotating body detection, optical tweezers, laser processing, super-resolution imaging etc. Hence, the advancement of OAM beam-generation technology and the enhancement of its technical proficiency and characterization capabilities are of paramount importance. These endeavours will not only facilitate the use of OAM beams in the aforementioned sectors but also extend the scope of applications in diverse fields related to OAM beams. At the FERMI Free-Electron Laser (Trieste, Italy), OAM beams are generated either by tailoring the emission process on the undulator side or, in most cases, by coupling a spiral zone plate (SZP) in tandem with the refocusing Kirkpatrick–Baez active optic system (KAOS). To provide a robust and reproducible workflow to users, a Hartmann wavefront sensor (WFS) is used for both optics tuning and beam characterization. KAOS is capable of delivering both tightly focused and broad spots, with independent control over vertical and horizontal magnification. This study explores a novel non-conventional `near collimation' operational mode aimed at generating beams with OAM that employs the use of a lithographically manufactured SZP to achieve this goal. The article evaluates the mirror's performance through Hartmann wavefront sensing, offers a discussion of data analysis methodologies, and provides a quantitative analysis of these results with ptychographic reconstructions. Keywords: tailored photonics beams, orbital angular momentum of light, wavefront sensing, ptychography Published in RUNG: 19.08.2024; Views: 629; Downloads: 3 Full text (10,31 MB) This document has many files! More... |
2. Topological properties and self-energy effects in elemental YbPolina M. Sheverdyaeva, F. Offi, Sandra Gardonio, Luka Novinec, M. I. Trioni, D. Ceresoli, S. Iacobucci, A. Ruocco, Giovanni Stefani, L. Petaccia, 2021, original scientific article Keywords: electronic structure, topological materials, lanthanides, angle-resolved photoemission spectroscopy Published in RUNG: 03.12.2021; Views: 2380; Downloads: 39 Link to full text This document has many files! More... |
3. STUDY OF ELECTRONIC STATES OF THIN METAL FILMS ON HEAVY METAL SURFACES : MASTER'S THESISLuka Novinec, 2018, master's thesis Abstract: V magistrskem delu smo se osredoto£ili na pripravo in karakterizacijo
heterogenih ve£plastnih tankih filmov sestavljenih iz kovin ter teºkih kovin.
Za izdelavo vzorcev smo izbrali dve feromagnetni kovini, Fe in Gd, ter
eno divalentno kovino iz redkih zemelj, Yb. Tanke filme smo nana²ali na
kristalno povr²ino volframa W(110) ter molibdena Mo(110). V primeru Fe
na povr²ini W(110) in Mo(110) ter Yb na pov²ini Mo(110) smo uspe²no
dolo£ili pogoje, potrebne za nana²anje atomsko enakomernih filmov. S pomo
£jo kotno odvisne fotoemisije smo preu£evali kvantna stanja v Fe in Yb
filmih na Mo in W kristalih. Celotno eksperimentalno delo je potekalo na
ºarkovnih linijah VUV-Photoemission in²tituta (ISM-CNR) ter BaDElPh
pri sinhrotronu Elettra v Trstu. Keywords: electronic states, thin metal films, heavy metal surfaces Published in RUNG: 04.12.2019; Views: 4908; Downloads: 115 Full text (25,10 MB) |
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