Complex Attosecond Waveform Synthesis at FEL FERMI

Free-electron lasers (FELs) can produce radiation in the short wavelength range extending from the extreme ultraviolet (XUV) to the X-rays with a few to a few tens of femtoseconds pulse duration. These facilities have enabled significant breakthroughs in the field of atomic, molecular, and optical physics, implementing different schemes based on two-color photoionization mechanisms. In this article, we present the generation of attosecond pulse trains (APTs) at the seeded FEL FERMI using the beating of multiple phase-locked harmonics. We demonstrate the complex attosecond waveform shaping of the generated APTs, exploiting the ability to manipulate independently the amplitudes and the phases of the harmonics. The described generalized attosecond waveform synthesis technique with an arbitrary number of phase-locked harmonics will allow the generation of sub-100 as pulses with programmable electric fields.

Download Full-text

Compact bolometric radiometer for free-electron lasers in a wavelength range from extreme-ultraviolet to x-rays

Optics Letters ◽

10.1364/ol.42.004776 ◽

2017 ◽

Vol 42 (22) ◽

pp. 4776 ◽

Cited By ~ 4

Author(s):

Takahiro Tanaka ◽

Masahiro Kato ◽

Norio Saito ◽

Shigeki Owada ◽

Kensuke Tono ◽

...

Keyword(s):

Wavelength Range ◽

Free Electron ◽

Extreme Ultraviolet ◽

X Rays ◽

Free Electron Lasers

Download Full-text

An X-ray gas monitor for free-electron lasers

Journal of Synchrotron Radiation ◽

10.1107/s1600577519005174 ◽

2019 ◽

Vol 26 (4) ◽

pp. 1092-1100 ◽

Cited By ~ 9

Author(s):

Andrey A. Sorokin ◽

Yilmaz Bican ◽

Susanne Bonfigt ◽

Maciej Brachmanski ◽

Markus Braune ◽

...

Keyword(s):

Spectral Range ◽

Pulse Energy ◽

Free Electron ◽

Extreme Ultraviolet ◽

X Rays ◽

Free Electron Lasers ◽

Beam Position ◽

X Ray ◽

Relative Standard ◽

Photon Pulse

A novel X-ray gas monitor (XGM) has been developed which allows the measurement of absolute photon pulse energy and photon beam position at all existing and upcoming free-electron lasers (FELs) over a broad spectral range covering vacuum ultraviolet (VUV), extreme ultraviolet (EUV) and soft and hard X-rays. The XGM covers a wide dynamic range from spontaneous undulator radiation to FEL radiation and provides a temporal resolution of better than 200 ns. The XGM consists of two X-ray gas-monitor detectors (XGMDs) and two huge-aperture open electron multipliers (HAMPs). The HAMP enhances the detection efficiency of the XGM for low-intensity radiation down to 105 photons per pulse and for FEL radiation in the hard X-ray spectral range, while the XGMD operates in higher-intensity regimes. The relative standard uncertainty for measurements of the absolute photon pulse energy is well below 10%, and down to 1% for measurements of relative pulse-to-pulse intensity on pulses with more than 1010 photons per pulse. The accuracy of beam-position monitoring in the vertical and horizontal directions is of the order of 10 µm.

Download Full-text

Table-top extreme ultraviolet second harmonic generation

Science Advances ◽

10.1126/sciadv.abe2265 ◽

2021 ◽

Vol 7 (21) ◽

pp. eabe2265

Author(s):

Tobias Helk ◽

Emma Berger ◽

Sasawat Jamnuch ◽

Lars Hoffmann ◽

Adeline Kabacinski ◽

...

Keyword(s):

Second Harmonic Generation ◽

Harmonic Generation ◽

First Principles ◽

Extreme Ultraviolet ◽

Second Harmonic ◽

High Harmonic ◽

Electronic Structure Calculations ◽

Free Electron Lasers ◽

X Ray ◽

Structure Calculations

The lack of available table-top extreme ultraviolet (XUV) sources with high enough fluxes and coherence properties has limited the availability of nonlinear XUV and x-ray spectroscopies to free-electron lasers (FELs). Here, we demonstrate second harmonic generation (SHG) on a table-top XUV source by observing SHG near the Ti M2,3 edge with a high-harmonic seeded soft x-ray laser. Furthermore, this experiment represents the first SHG experiment in the XUV. First-principles electronic structure calculations suggest the surface specificity and separate the observed signal into its resonant and nonresonant contributions. The realization of XUV-SHG on a table-top source opens up more accessible opportunities for the study of element-specific dynamics in multicomponent systems where surface, interfacial, and bulk-phase asymmetries play a driving role.

Download Full-text

An Improved Collimator for Extreme Ultraviolet and X Rays

Review of Scientific Instruments ◽

10.1063/1.1684098 ◽

1969 ◽

Vol 40 (7) ◽

pp. 894-896 ◽

Cited By ~ 4

Author(s):

J. H. Underwood

Keyword(s):

Extreme Ultraviolet ◽

X Rays

Download Full-text

The output of a laser amplifier with simultaneous amplified spontaneous emission and an injected seed

Laser and Particle Beams ◽

10.1017/s0263034609000500 ◽

2009 ◽

Vol 27 (3) ◽

pp. 393-398 ◽

Cited By ~ 6

Author(s):

H. Huang ◽

G.J. Tallents

Keyword(s):

Spontaneous Emission ◽

Extreme Ultraviolet ◽

Amplified Spontaneous Emission ◽

Gain Saturation ◽

Free Electron Lasers ◽

Laser Amplifier ◽

One Dimensional ◽

X Ray ◽

Laser Amplifiers ◽

Harmonic Radiation

AbstractThe minimum irradiance needed to overcome amplified spontaneous emission (ASE) of a seed beam injected into a laser amplifier is evaluated. The treatment is particularly applicable to extreme ultraviolet (EUV) and X-ray laser schemes to inject laser harmonic radiation as a seed into (1) plasma laser amplifiers and (2) free-electron lasers. Simple expressions and calculations are given for the minimum injected irradiance required for amplification of the injected seed beam to exceed ASE from the amplifier, including the effects of gain saturation, assuming one dimensional radiative transfer.

Download Full-text

Switching of the harmonic order in free-electron lasers by controlling the density modulation of an electron bunch

Journal of Synchrotron Radiation ◽

10.1107/s1600577518008937 ◽

2018 ◽

Vol 25 (5) ◽

pp. 1317-1322 ◽

Cited By ~ 1

Author(s):

Norihiro Sei ◽

Hiroshi Ogawa ◽

QiKa Jia

Keyword(s):

Free Electron ◽

Free Electron Laser ◽

Extreme Ultraviolet ◽

Free Electron Lasers ◽

Harmonic Order ◽

Third Harmonic ◽

X Ray ◽

The Third ◽

Density Modulation ◽

Higher Harmonic

It was demonstrated that harmonic order in free-electron laser (FEL) oscillations could be switched by adjusting the dispersive gap of the optical klystron ETLOK-III in the storage ring NIJI-IV. The effective gains for the fundamental and third-harmonic FEL oscillations were evaluated and it was confirmed that the FEL oscillated at the order of the harmonic with the higher effective gain. The ratio between the effective gain for the fundamental and that for the third harmonic was controlled by the dispersive gap. It was also demonstrated that a spectral measurement of the FEL-based Compton scattering X-ray beam was effective for directly observing the switching of the harmonic order. These results contribute to the development of higher-harmonic FEL oscillations suppressing the fundamental FEL oscillation in the extreme ultraviolet and X-ray regions.

Download Full-text

Laser-driven compact free electron laser: from extreme ultraviolet radiation to x-rays

High Power Lasers and Applications ◽

10.1117/12.2591994 ◽

2021 ◽

Author(s):

Alexander Molodozhentsev ◽

Konstantin Kruchinin ◽

Gabriele M. Grittani ◽

Tyler Green ◽

Jaroslav Nejdl ◽

...

Keyword(s):

Ultraviolet Radiation ◽

Free Electron ◽

Free Electron Laser ◽

Extreme Ultraviolet ◽

X Rays ◽

Extreme Ultraviolet Radiation

Download Full-text

Stellar flares versus luminosity: XUV-induced atmospheric escape and planetary habitability

Monthly Notices of the Royal Astronomical Society Letters ◽

10.1093/mnrasl/slaa166 ◽

2020 ◽

Vol 500 (1) ◽

pp. L1-L5

Author(s):

Dimitra Atri ◽

Shane R Carberry Mogan

Keyword(s):

Extreme Ultraviolet ◽

Wide Energy Range ◽

X Rays ◽

Loss Mechanism ◽

Atmospheric Escape ◽

Stellar Flares ◽

Wide Energy ◽

A Minor ◽

Atmospheric Loss ◽

Planetary Habitability

ABSTRACT Space weather plays an important role in the evolution of planetary atmospheres. Observations have shown that stellar flares emit energy in a wide energy range (1030–1038 erg), a fraction of which lies in X-rays and extreme ultraviolet (XUV). These flares heat the upper atmosphere of a planet, leading to increased escape rates, and can result in atmospheric erosion over a period of time. Observations also suggest that primordial terrestrial planets can accrete voluminous H/He envelopes. Stellar radiation can erode these protoatmospheres over time, and the extent of this erosion has implications for the planet’s habitability. We use the energy-limited equation to calculate hydrodynamic escape rates from these protoatmospheres irradiated by XUV stellar flares and luminosity. We use the flare frequency distribution of 492 FGKM stars observed with TESS to estimate atmospheric loss in habitable zone planets. We find that for most stars, luminosity-induced escape is the main loss mechanism, with a minor contribution from flares. However, flares dominate the loss mechanism of ∼20 per cent M4–M10 stars. M0–M4 stars are most likely to completely erode both their proto- and secondary atmospheres, and M4–M10 are least likely to erode secondary atmospheres. We discuss the implications of these results on planetary habitability.

Download Full-text

High Repetition Rate and Coherent Free-Electron Laser in the X-Rays Range Tailored for Linear Spectroscopy

Instruments ◽

10.3390/instruments3030047 ◽

2019 ◽

Vol 3 (3) ◽

pp. 47 ◽

Cited By ~ 1

Author(s):

Vittoria Petrillo ◽

Michele Opromolla ◽

Alberto Bacci ◽

Illya Drebot ◽

Giacomo Ghiringhelli ◽

...

Keyword(s):

Free Electron ◽

Repetition Rate ◽

Free Electron Laser ◽

Extreme Ultraviolet ◽

High Harmonic ◽

High Repetition Rate ◽

X Rays ◽

Regenerative Amplifier ◽

X Ray ◽

High Repetition

Fine time-resolved analysis of matter—i.e., spectroscopy and photon scattering—in the linear response regime requires fs-scale pulsed, high repetition rate, fully coherent X-ray sources. A seeded Free Electron Laser (FEL) driven by a Linac based on Super Conducting cavities, generating 10 8 – 10 10 coherent photons at 2–5 keV with 0.2–1 MHz of repetition rate, can address this need. Three different seeding schemes, reaching the X-ray range, are described hereafter. The first two are multi-stage cascades upshifting the radiation frequency by a factor of 10–30 starting from a seed represented by a coherent flash of extreme ultraviolet light. This radiation can be provided either by the High Harmonic Generation of an optical laser or by an FEL Oscillator operating at 12–14 nm. The third scheme is a regenerative amplifier working with X-ray mirrors. The whole chain of the X-ray generation is here described by means of start-to-end simulations.

Download Full-text