Related papers: Self-Seeded Free-Electron Lasers with Orbital Angu…
X-ray free-electron lasers (XFELs) utilize high-density and high-energy electron bunches which are well-suited to produce Compton back-scattering radiation. Here we study back-scattered radiation pulses produced by the interaction of XFEL…
Seeded free-electron lasers (FELs) capable of operating at repetition rates up to the MHz level are in high demand for advanced time-resolved spectroscopies, which require both full longitudinal coherence and high average photon flux in the…
The generation of attosecond X-ray pulses has garnered significant attention within the X-ray free-electron laser (FEL) community due to their potential for ultrafast time-resolved studies. Such pulses enable the investigation of electron…
We report the experimental demonstration of direct-amplification enabled harmonic generation in an ultraviolet free-electron laser (FEL) driven by a low-intensity seed laser. By employing a versatile undulator configuration that enables…
Orbital angular momentum (OAM) light beams for high-order harmonic generation (HHG) provide an additional degree of freedom to study the light-matter interaction at ultrafast timescales. A more sophisticated configuration is a perfect…
With the increasing demand for potential applications in almost all fields in modern optics, the generation of vortex beams has attracted significant interest. Based on a flat plate made of electro-optical crystals, we propose an…
Intense laser ionization expands Einstein's photoelectric effect rules giving a wealth of phenomena widely studied over the last decades. In all cases, so far, photons were assumed to carry one unit of angular momentum. However it is now…
We put forward a co-axial pump(optical)-probe(X-rays) experimental concept and show performance of the optical component. A Bessel beam generator with a central 100 micrometers-diameter hole (on the optical axis) was fabricated using…
Free-electron lasers (FELs) generate the brightest coherent X-ray pulses available, enabling atomic-resolution and femtosecond-timescale studies across physics, chemistry, and biology. Realising their full potential at extreme peak powers…
Besides a linear momentum, optical fields carry an angular momentum (AM), which have two intrinsic components: one is spin angular momentum (SAM) related to the polarization state of the field, and the other is orbital angular momentum…
The ability to arbitrarily dial in amplitudes and phases enables the fundamental quantum state operations pioneered for microwaves and then infrared and visible wavelengths during the second half of the last century. Self-seeded X-ray…
We study the perspectives of measuring the phenomenon of vacuum birefringence predicted by quantum electrodynamics using an x-ray free-electron laser (XFEL) alone. We devise an experimental scheme allowing the XFEL beam to collide with…
In light optics, beams with orbital angular momentum (OAM) can be produced by employing a properly-tuned two-cylinder-lens arrangement, also called $\pi$/2 mode converter. It is not possible to convey this concept directly to the beam in an…
We propose and analyze a novel regenerative amplifier free electron laser (FEL) to produce fully coherent x-ray pulses. The method makes use of narrow-bandwidth Bragg crystals to form an x-ray feedback loop around a relatively short…
Breaking the diffraction limit and focusing laser beams to subwavelength scale are becoming possible with the help of recent developments in plasmonics. Such subwavelength focusing bridges different length scales of laser beams and matter.…
The physics of coherent beams of photons carrying axial orbital angular momentum (OAM) is well understood and such beams, sometimes known as vortex beams, have found applications in optics and microscopy. Recently electron beams carrying…
X-ray beams with orbital angular momentum (OAM) are a promising tool for x-ray characterization techniques. Beams with OAM have a helicity--an azimuthally varying phase--which leads to a gradient of the light field. New material properties…
Recently, the self-modulation scheme of a weakly pre-bunched electron beam has been proposed [Yan et al., Physical Review Letters 126, 084801 (2021)], which is of great promise for high-repetition-rate seeded free-electron lasers (FELs),…
We identify and explore a high orbital angular momentum (OAM) harmonics generation and amplification mechanism that manipulates the OAM independently of any other laser property, by preserving the initial laser wavelength, through…
High-brightness femtosecond-to-attosecond pulses are indispensable for probing electron dynamics on their fundamental temporal scales. X-ray free-electron lasers (XFELs) at high repetition rates will facilitate high-statistics measurements…