Journal: Structural Dynamics

Article Title: High-repetition-rate ultrafast electron diffraction with direct electron detection

doi: 10.1063/4.0000256

Figure Lengend Snippet: Electron diffraction patterns of (a) 11-nm monocrystalline gold (Au) and (b) 31-nm polycrystalline aluminum (Al) measured using a 95-keV electron pulse containing ∼100 electrons at 30-kHz with a direct electron detector. Both data were measured without apertures. Insets: measured detector images, with simulated data shown for aluminum.

Article Snippet: The reciprocal-space resolution and transverse coherence length of our instrument were characterized experimentally by measuring the electron diffraction pattern from a monocrystalline gold film (Plano GmbH, 11 nm) and a polycrystalline aluminum film (Plano GmbH, 31-nm) using a 95-keV electron pulse containing ∼100 electrons on-target.

Techniques:

Journal: Structural Dynamics

Article Title: High-repetition-rate ultrafast electron diffraction with direct electron detection

doi: 10.1063/4.0000256

Figure Lengend Snippet: Saturation effects in DECTRIS QUADRO direct electron detector. (a1)–(a8) Detector images measured with a different number of electrons per pulse as indicated at the top of images 1–8. Exposure time of 0.1 s was used. (b) Detector image of dark current contribution with a colourmap scaling that was multiplied by a factor of 10 relative to that of image a1. Exposure time of 0.1 s was used. (c1)–(c3) Detector images of an electron beam containing 10 2 electrons measured with different exposure times. (d) Vertical beam profile of the primary unscattered electron beam after interaction with an 11-nm monocrystalline gold sample using an electron pulse containing different numbers of electrons. (e) and (f) Radial distribution of electron beam measured with different exposure times using an electron beam containing (d) 10 2 electrons and (e) 10 4 electrons. (g)–(i) Radial distributions of Bragg diffraction peaks from the sample corresponding to data from panels (d)–(f). Panel (g) was normalized to the sum of the total intensity corresponding to a radius of 30–200 pixels for a like-for-like comparison of data measured with different number of electrons. Panels (a), (b), (d), and (g) were averaged over 100 images, while all other panels were measured with a single image.

Article Snippet: The reciprocal-space resolution and transverse coherence length of our instrument were characterized experimentally by measuring the electron diffraction pattern from a monocrystalline gold film (Plano GmbH, 11 nm) and a polycrystalline aluminum film (Plano GmbH, 31-nm) using a 95-keV electron pulse containing ∼100 electrons on-target.

Techniques: Comparison

Journal: Structural Dynamics

Article Title: High-repetition-rate ultrafast electron diffraction with direct electron detection

doi: 10.1063/4.0000256

Figure Lengend Snippet: Shot-to-shot correction of electron beam pointing and intensity jitter with sub-pixel accuracy. Summed detector image of electron beam (a) before any correction, (b) after intensity jitter correction, and (c) after intensity and pointing jitter correction with sub-pixelation of factor 10. The images shown were summed over ∼40 000 shots corresponding to the data shown in . (d) Radial distribution of primary unscattered electron beam before and after correction. (e) and (f) Radial distribution of Bragg diffraction peaks from 11-nm monocrystalline gold before and after correction.

Article Snippet: The reciprocal-space resolution and transverse coherence length of our instrument were characterized experimentally by measuring the electron diffraction pattern from a monocrystalline gold film (Plano GmbH, 11 nm) and a polycrystalline aluminum film (Plano GmbH, 31-nm) using a 95-keV electron pulse containing ∼100 electrons on-target.

Techniques: