1. Advantages and disadvantages of experiments with ultrashort two-color pulsesMatija Stupar, 2020, doctoral dissertation Abstract: Advances in the development of lasers have led to a new class of radiation sources generating coherent, tunable, ultrashort light pulses in the spectral region ranging from infrared to soft X-rays. This includes high-order harmonics generation in gas (HHG), on which relies the CITIUS facility at University of Nova Gorica (Slovenia), and free-electron lasers (FELs), such as the facility FERMI at Elettra-Sincrotrone Trieste (Italy). The distinctive structure of HHG and FEL radiation paved the way to time-resolved experiments, which are performed to investigate events occurring on a short, or very short, temporal scale, from picoseconds to femtoseconds.
This work focuses on the advantages and disadvantages of some experimental techniques based on using these novel light sources to investigate the microscopic and/or ultrafast dynamics of matter samples, which have been previously driven out of equilibrium.
Advantages rely on the implementation of various applications based on two-color schemes and, more specifically, include the possibility of acquiring two-dimensional frequency maps, measuring electrons’ effective masses, or investigating electronic properties decoupled from the influence of the lattice. Particular focus will be put on experimental methods relying on photoelectric effect and photoelectron spectroscopy. In all experiments, we took advantage of one or more specific properties of HHG and FEL sources, such as controllable chirp, to study laser dressed states in helium, variable polarization, to study electronic properties of iron-based pnictides and ultrashort pulses (< 10 fs) to study the purely electronic dynamics in transition metal dichalcogenides.
On the other hand, the study of the interface between a molecule and a topological insulator revealed some intrinsic limitations and physical drawbacks of the technique, such as spurious effects originating from the high power pulses, like multiphoton absorption and the space charge effect, or the reduction of experimental resolution when pushing for shorter and shorter pulse durations. Some disadvantages are also connected to the current state-of-the-art in the field of ultrashort laser systems, where a trade-off needs to be found between repetition rate and laser power.
Finally, state-of-the-art experiments based on the ability to generate ultrashort pulses carrying orbital angular momentum in visible, near-infrared as well as extreme UV range will be presented. The use of these pulses opens the door to the investigation of new physical phenomena, such as probing magnetic vortices using extreme ultraviolet light from a free-electron laser or imprinting the spatial distribution of an ultrashort infrared pulse carrying orbital angular momentum onto a photoelectron wave packet. Keywords: ultrafast lasers, two-color experiments, photoemission, high-order harmonic generation, free-electron lasers, hot-electrons dynamics, surface science, pump-probe photoemission, ultraviolet photoemission, orbital angular momentum Published in RUNG: 02.12.2020; Views: 5136; Downloads: 142 Full text (19,78 MB) |
2. Spectrotemporal control of soft x-ray laser pulsesNajmeh S. Miria, Enrico Allaria, Niky Bruchon, Paolo Cinquegrana, Miltcho Bojanov Danailov, Giovanni De Ninno, S. Di Mitri, Eugenio Ferrari, Luca Giannessi, Primož Rebernik Ribič, 2020, original scientific article Keywords: coherent control, free electron lasers, echo-enabled harmonic generation Published in RUNG: 15.06.2020; Views: 3788; Downloads: 81 Link to full text |
3. Status and perspectives of the FERMI FEL facility (2019)Luca Giannessi, Enrico Allaria, Laura Badano, S. Bassanese, Filippo Bencivenga, Carlo Callegari, Flavio Capotondi, Davide Castronovo, F. Cilento, Paolo Cinquegrana, Giovanni De Ninno, Primož Rebernik Ribič, 2019, published scientific conference contribution Keywords: free-electron lasers, harmonic generation Published in RUNG: 15.01.2020; Views: 3770; Downloads: 96 Link to full text This document has many files! More... |
4. User operation of sub-picosecond thz coherent transition radiation parasitic to a VUV FELS. Di Mitri, N. Adhlakha, Enrico Allaria, Laura Badano, Giovanni De Ninno, P. Di Pietro, G. Gaio, Luca Giannessi, G. Penco, A. Perucchi, Primož Rebernik Ribič, 2019, published scientific conference contribution Keywords: free-electron lasers, coherent transition radiation, electron beam manipulation Published in RUNG: 15.01.2020; Views: 3878; Downloads: 89 Link to full text This document has many files! More... |
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6. First lasing of a free electron laser in the soft x-ray spectral range with echo enabled harmonic generationEnrico Allaria, Alessandro Abrami, Laura Badano, Maurizio Bossi, Flavio Capotondi, Davide Castronovo, Marco Cautero, Paolo Cinquegrana, Ivan Cudin, M. B. Danailov, Primož Rebernik Ribič, Giovanni De Ninno, 2019, published scientific conference contribution Keywords: free-electron lasers, harmonic generation Published in RUNG: 15.01.2020; Views: 3838; Downloads: 92 Link to full text |
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8. Beyond the limits of 1D coherent synchrotron radiationA. D. Brynes, P. Smorenburg, I. Akkermans, Enrico Allaria, Laura Badano, S. Brussaard, M. B. Danailov, Alexander Demidovich, Giovanni De Ninno, David Gauthier, Primož Rebernik Ribič, 2018, original scientific article Keywords: coherent synchrotron radiation, free electron lasers, accelerators Published in RUNG: 14.01.2020; Views: 4009; Downloads: 81 Link to full text |
9. Pulse duration of seeded free-electron lasersPaola Finetti, Hauke Höppner, Enrico Allaria, Carlo Callegari, Flavio Capotondi, Paolo Cinquegrana, Marcello Coreno, Riccardo Cucini, Miltcho Bojanov Danailov, Alexander Demidovich, Giovanni De Ninno, Primož Rebernik Ribič, 2017, original scientific article Keywords: free-electron lasers, harmonic generation, pulse duration Published in RUNG: 14.01.2020; Views: 3877; Downloads: 14 Link to full text |
10. High resolution beam profiling of X-ray free electron laser radiation by polymer imprint developmentBenedikt Rosner, Florian Döring, Primož Rebernik Ribič, David Gauthier, Emiliano Principi, Claudio Masciovecchio, Marco Zangrando, Joan Vila-Comamala, Giovanni De Ninno, Christian David, 2017, original scientific article Keywords: free-electron lasers, metrology, polymers, X-ray optics Published in RUNG: 13.01.2020; Views: 3886; Downloads: 0 |