Publications by authors named "G M H Knippels"

The ability of electron microscopes to analyze all the atoms in individual nanostructures is limited by lens aberrations. However, recent advances in aberration-correcting electron optics have led to greatly enhanced instrument performance and new techniques of electron microscopy. The development of an ultrastable electron microscope with aberration-correcting optics and a monochromated high-brightness source has significantly improved instrument resolution and contrast.

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Subpicosecond synchronization between a mirror-dispersion-controlled 10-fs Ti:sapphire laser and the Free-Electron Laser for Infrared Experiments has been achieved. The measured intensity cross correlation between the two lasers is consistent with a jitter of only 400 fs rms. The wide and continuous tunability of the free-electron laser (FEL; 4.

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Phase-matched second-harmonic generation is obtained in various LiInS(2) crystals by use of the tunable picosecond output of the free-electron laser for infrared experiments (FELIX) as the pump source in the mid-IR range from 2.75 to 6.0 microm.

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We report subpicosecond electro-optic measurements of the length of individual relativistic electron bunches. The longitudinal electron-bunch shape is encoded electro-optically on to the spectrum of a chirped laser pulse. The electron-bunch length is determined by analyzing individual laser-pulse spectra obtained with and without the presence of an electron bunch.

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Article Synopsis
  • The study focuses on the shape of picosecond optical pulses generated by free-electron laser (FEL) oscillators, specifically how varying cavity detuning affects their characteristics.
  • For significant cavity detuning, the leading edge of the optical pulse exhibits an exponential form, influenced by both the cavity's detuning and its quality factor.
  • These findings are crucial for designing new infrared FEL facilities, as they help balance the need for short pulse durations with narrow spectral bandwidth essential for various spectroscopy techniques.
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