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arXiv · 1702.02029

Tunable Ampere phase plate for low dose imaging of biomolecular complexes

Amir H. Tavabi·Marco Beleggia·Vadim Migunov·Alexey Savenko·Sara Sandin·Ozan Öktem·Rafal E. Dunin-Borkowski·Giulio Pozzi
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Abstract

A novel device that can be used as a tunable support-free phase plate for transmission electron microscopy of weakly scattering specimens is described. The device relies on the generation of a controlled phase shift by the magnetic field of a segment of current-carrying wire that is oriented parallel or antiparallel to the electron beam. The validity of the concept is established using both experimental electron holographic measurements and a theoretical model based on Ampere's law. Computer simulations are used to illustrate the resulting contrast enhancement for studies of biological cells and macromolecules.

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Amir H. Tavabi, Marco Beleggia, Vadim Migunov, Alexey Savenko, Sara Sandin, Ozan Öktem, Rafal E. Dunin-Borkowski, Giulio Pozzi. 2017-02-02. Tunable Ampere phase plate for low dose imaging of biomolecular complexes. https://arxiv.org/abs/1702.02029

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