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arXiv · 1808.00370

Interpretable and efficient contrast in scanning transmission electron microscopy with a diffraction grating beamsplitter

Tyler R. Harvey·Fehmi S. Yasin·Jordan J. Chess·Jordan S. Pierce·Roberto M. S. dos Reis·Vasfi Burak Özdöl·Peter Ercius·Jim Ciston·Wenchun Feng·Nicholas A. Kotov·Benjamin J. McMorran·Colin Ophus
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Abstract

Efficient imaging of biomolecules, 2D materials and electromagnetic fields depends on retrieval of the phase of transmitted electrons. We demonstrate a method to measure phase in a scanning transmission electron microscope using a nanofabricated diffraction grating to produce multiple probe beams. The measured phase is more interpretable than phase-contrast scanning transmission electron microscopy techniques without an off-axis reference wave, and the resolution could surpass that of off-axis electron holography. We apply the technique to image nanoparticles, carbon sub- strates and electric fields. The contrast observed in experiments agrees well with contrast predicted in simulations.

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Tyler R. Harvey, Fehmi S. Yasin, Jordan J. Chess, Jordan S. Pierce, Roberto M. S. dos Reis, Vasfi Burak Özdöl, Peter Ercius, Jim Ciston, Wenchun Feng, Nicholas A. Kotov, Benjamin J. McMorran, Colin Ophus. 2018-07-28. Interpretable and efficient contrast in scanning transmission electron microscopy with a diffraction grating beamsplitter. https://doi.org/10.1103/physrevapplied.10.061001

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