A5088888010- Particle Accelerators and Free-Electron Lasers
- Advanced X-ray Imaging Techniques
- Particle accelerators and beam dynamics
- Laser-Matter Interactions and Applications
- Gyrotron and Vacuum Electronics Research
- Advanced Electron Microscopy Techniques and Applications
- Laser-Plasma Interactions and Diagnostics
- Laser Design and Applications
- Quantum Information and Cryptography
- Superconducting Materials and Applications
- Photocathodes and Microchannel Plates
- Particle Detector Development and Performance
- International Science and Diplomacy
- Magnetic properties of thin films
- Atomic and Molecular Physics
- Advanced Fiber Laser Technologies
- Quantum, superfluid, helium dynamics
- Optical Coatings and Gratings
- Advanced Surface Polishing Techniques
- Photonic and Optical Devices
- Radiation Detection and Scintillator Technologies
- Medical Imaging Techniques and Applications
- Digital Radiography and Breast Imaging
- Scientific Computing and Data Management
- Nuclear Physics and Applications
Elettra-Sincrotrone Trieste S.C.p.A.
2015-2024
AREA Science Park
2013
University of Genoa
1993
Abstract Rabi oscillations are periodic modulations of populations in two-level systems interacting with a time-varying field 1 . They ubiquitous physics applications different areas such as photonics 2 , nano-electronics 3 electron microscopy 4 and quantum information 5 While the theory developed by was intended for fermions gyrating magnetic fields, Autler Townes realized that it could also be used to describe coherent light–matter interactions within rotating-wave approximation 6 Although...
Quantum entanglement between the degrees of freedom encountered in classical world is challenging to observe due surrounding environment. To elucidate this issue, we investigate generated over ultrafast timescales a bipartite quantum system comprising two massive particles: free-moving photoelectron, which expands mesoscopic length scale, and light-dressed atomic ion, represents hybrid state light matter. Although photoelectron spectra are measured classically, allows us reveal information...
Quantum mechanically, photoionization can be fully described by the complex amplitudes that describe transition between ground state and continuum state. Knowledge of value phase these has been a central interest in studies newly developing attosecond science, since reveal important information about phenomena such as electron correlation. We present new attosecond-precision interferometric method angle-resolved measurement for amplitudes, using two phase-locked Extreme Ultraviolet pulses...
The FERMI@Elettra project is a seeded free electron laser (FEL) source, based on the High Gain Harmonic Generation (HGHG) scheme. It designed to supply photons in spectral range from 65 20 nm with first undulator line (FEL-1) and 4 second (FEL-2). After period of commissioning beam up 100 MeV at low charge, started August 2009, several phases installations periods have been alternated through 2010. On December 2010 FEL light FEL-1 was obtained 43 by adopting as an initial seed third harmonic...
An understanding of collective effects is fundamental importance for the design and optimisation performance modern accelerators. In particular, an accelerator with strict requirements on beam quality, such as a free electron laser (FEL), highly dependent correspondence between simulation, theory experiments in order to correctly account effect coherent synchrotron radiation (CSR), other effects. A traditional approach simulation codes utilise analytic one-dimensional approximation CSR...
Intense, mutually coherent beams of multiharmonic extreme ultraviolet light can now be created using seeded free-electron lasers, and the phase difference between harmonics tuned with attosecond accuracy. However, absolute value is generally not determined. We present a method for determining precisely relationship fundamental wavelength its second harmonic, as well amplitude ratio. Only few easily calculated theoretical parameters are required in addition to experimental data.Received 27...
We demonstrate that emission of coherent transition radiation by a ∼1 GeV energy-electron beam passing through an Al foil is enhanced in intensity and extended frequency spectral range, the energy correlation established along synchrotron wakefield, presence proper electron optics delivery system. Analytical numerical models, based on experimental parameters collected at FERMI free laser (FEL), predict with two peaks ∼0.3 THz ∼1.5 THz, extending up to 8.5 above 20 dB w.r.t. main peak. Up...
The advent of free-electron lasers (FELs) in the soft- and hard-x-ray spectral regions has introduced possibility to probe electronic, magnetic, structural dynamics, both diluted condensed matter samples, with femtosecond time resolution. In particular, FELs have strongly enhanced capabilities several analytical techniques, which taken advantage high degree transverse coherence provided. Free-electron based on harmonic up-conversion an external coherent source (seed) are characterized also...
The microbunching instability has been a long-standing issue for high-brightness free-electron lasers (FELs) and is significant showstopper to achieve full longitudinal coherence in the x-ray regime. This paper reports first experimental demonstration of mitigation through transverse Landau damping, based on linear optics control dispersive region. Analytical predictions content are supported by numerical calculations gain. effect confirmed characterization spectral brightness FERMI FEL...
We have generated elliptically polarized femtosecond pulses from a seeded free-electron laser (FEL) in the spectral range 700–800 eV and conducted demonstrative experiments based on magnetic circular dichroism, at Fe L3 edge. This was achieved by making use of radiation produced third harmonic fundamental FEL wavelength λ. A planar radiator emits linearly harmonics along undulator axis, while helical produces off-axis with polarization. However, circularly light is characterized rather low...
Abstract Single-photon laser enabled Auger decay (spLEAD) is an electronic de-excitation process which was recently predicted and observed in Ne. We have investigated it using bichromatic phase-locked free electron radiation extensive angle-resolved photoelectron measurements, supported by a detailed theoretical model. first used separately the fundamental wavelength resonant with Ne + 2 s –2 p transition, 46.17 nm, its second harmonic, 23.08 then their combination. In latter case phase...
Abstract The optimal performance of high-brightness free-electron lasers (FELs) is limited by the microbunching instability, which can cause variations in both slice energy spread and longitudinal profile electron beams. In this paper, we perform 2D Fourier analysis full bunch phase space, such that modulations planes be studied simultaneously. Unlike standard 1D analysis, method able to reveal a folded would otherwise remain uncovered. Additionally, plasma oscillation between density also...
Extension of stable longitudinal coherence from vacuum ultraviolet to x rays is highly sought after in the free-electron laser (FEL) community, but it often prevented by bandwidth broadening originated electron beam microbunching instability. We demonstrate that a proper tuning linear optics before enters undulator mitigates microbunching-induced sideband The experiment was conducted at Fermi FEL operated echo-enabled harmonic generation mode, where spectral brightness 7 nm wavelength...
The FERMI Free Electron Laser (FEL) in Trieste, Italy operates the extreme ultraviolet and soft x rays (EUV-SXR) wavelength range delivering high-fluence, stable, ultra-short pulses. Its unique design based on a seeded scheme tunable undulators allows unprecedented control of pulse parameters such as wavelength, phase, polarization, synchronization, duration implementation multi-color FEL schemes. Both FEL-1 FEL-2 lines with nominal 100–20 nm 20–4 nm, respectively, are open to users. We...
We report on the observation of time-resolved quantum beats in helium fluorescence from transition 1s3p -> 1s2s, where initial state is excited by XUV free-electron laser radiation. The originate Zeeman splitting magnetic substates due to an external field. perform a systematic study this effect and discuss possibilities studying phenomenon x-ray regime.
High-brightness electron bunches, such as those generated and accelerated in free-electron lasers (FELs), can develop small-scale structure the longitudinal phase space. This causes variations slice energy spread current profile of bunch which then undergo amplification, an effect known microbunching instability. By imposing modulations on low-energy section accelerator, using undulator a modulated laser pulse center dispersive chicane, it is possible to manipulate allows for control study...
Echo-enabled harmonic generation free-electron lasers (EEHG FELs) are promising candidates to produce fully coherent soft x-ray pulses by virtue of efficient high-harmonic frequency up-conversion from ultraviolet lasers. The ultimate spectral limit EEHG, however, remains unclear, because the broadening and distortions induced in output spectrum residual broadband energy modulations electron beam. We present a mathematical description impact incoherent (broadband) on bunching produced...