title: Simultaneous atomic-resolution electron ptychography and Z-contrast imaging of light and heavy elements in complex nanostructures.
abstract: The aberration-corrected scanning transmission electron microscope (STEM) has emerged as a key tool for atomic resolution characterization of materials, allowing the use of imaging modes such as Z-contrast and spectroscopic mapping. The STEM has not been regarded as optimal for the phase-contrast imaging necessary for efficient imaging of light materials. Here, recent developments in fast electron detectors and data processing capability is shown to enable electron ptychography, to extend the capability of the STEM by allowing quantitative phase images to be formed simultaneously with incoherent signals. We demonstrate this capability as a practical tool for imaging complex structures containing light and heavy elements, and use it to solve the structure of a beam-sensitive carbon nanostructure. The contrast of the phase image contrast is maximized through the post-acquisition correction of lens aberrations. The compensation of defocus aberrations is also used for the measurement of three-dimensional sample information through post-acquisition optical sectioning.
authors: Department of Materials, University of Oxford, Parks Road, OX1 3PH Oxford, UK.
authors: H
authors: H
authors: Yang
authors: Department of Chemistry, University of Oxford, 12 Mansfield Road, OX1 3TA Oxford, UK.
authors: R N
authors: RN
authors: Rutte
authors: Department of Materials, University of Oxford, Parks Road, OX1 3PH Oxford, UK.
authors: L
authors: L
authors: Jones
authors: PNDetector GmbH, Sckellstrasse 3, 81667 München, Germany.
authors: M
authors: M
authors: Simson
authors: JEOL Ltd 3-1-2 Musashino Akishima, Tokyo 196-8558, Japan.
authors: R
authors: R
authors: Sagawa
authors: PNSensor GmbH, Otto-Hahn-Ring 6, 81739 München, Germany.
authors: H
authors: H
authors: Ryll
authors: PNDetector GmbH, Sckellstrasse 3, 81667 München, Germany.
authors: M
authors: M
authors: Huth
authors: Department of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria.
authors: T J
authors: TJ
authors: Pennycook
authors: Department of Chemistry, University of Oxford, 12 Mansfield Road, OX1 3TA Oxford, UK.
authors: M L H
authors: ML
authors: Green
authors: PNDetector GmbH, Sckellstrasse 3, 81667 München, Germany.
authors: H
authors: H
authors: Soltau
authors: JEOL Ltd 3-1-2 Musashino Akishima, Tokyo 196-8558, Japan.
authors: Y
authors: Y
authors: Kondo
authors: Department of Chemistry, University of Oxford, 12 Mansfield Road, OX1 3TA Oxford, UK.
authors: B G
authors: BG
authors: Davis
authors: Department of Materials, University of Oxford, Parks Road, OX1 3PH Oxford, UK.
authors: P D
authors: PD
authors: Nellist