Possibility of high-resolution ptychographic iterative imaging with low energy electrons: dynamical calculations.

Ptychographic iterative engine (PIE), a form of coherent diffractive imaging in which the phase of both low-angle and high-angle diffraction data is used to form an image without a lens, can in principle deliver wavelength-limited resolution. Working at low accelerating voltages (30 keV) reduces specimen knock-on damage, increases high-resolution contrast and allows a scanning electron microscope to be used as a transmission electron microscopy. However, electrons are very strongly scattered at low energy. To that end, the effect of dynamical scattering on PIE at low accelerating voltages is calculated to illustrate the possibility of generating high-resolution images with low energy electrons.

[1]  Leslie J. Allen,et al.  Deterministic electron ptychography at atomic resolution , 2014 .

[2]  J. Rodenburg,et al.  Optical ptychography: a practical implementation with useful resolution. , 2010, Optics letters.

[3]  A. G. Cullis,et al.  Hard-x-ray lensless imaging of extended objects. , 2007, Physical review letters.

[4]  J. Rodenburg.  Ptychography and Related Diffractive Imaging Methods , 2008 .

[5]  K. Nugent,et al.  Atom-scale ptychographic electron diffractive imaging of boron nitride cones. , 2012, Physical review letters.

[6]  Fucai Zhang,et al.  Superresolution imaging via ptychography. , 2011, Journal of the Optical Society of America. A, Optics, image science, and vision.

[7]  A. Krasheninnikov,et al.  Electron knock-on damage in hexagonal boron nitride monolayers , 2010 .

[8]  Zhong Lin Wang.  Thermal diffuse scattering in sub-angstrom quantitative electron microscopy-phenomenon, effects and approaches. , 2003, Micron.

[9]  S. Pennycook,et al.  Atom-by-atom structural and chemical analysis by annular dark-field electron microscopy , 2010, Nature.

[10]  Cheng Liu,et al.  Influence of thick crystal effects on ptychographic image reconstruction with moveable illumination. , 2009, Ultramicroscopy.

[11]  J. Rodenburg,et al.  An improved ptychographical phase retrieval algorithm for diffractive imaging. , 2009, Ultramicroscopy.

[12]  M F Crommie,et al.  Direct imaging of lattice atoms and topological defects in graphene membranes. , 2008, Nano letters.

[13]  H. Sawada,et al.  Visualizing and identifying single atoms using electron energy-loss spectroscopy with low accelerating voltage. , 2009, Nature chemistry.

[14]  Keita Kobayashi,et al.  Low voltage electron diffractive imaging of atomic structure in single-wall carbon nanotubes , 2011 .

[15]  J. Rodenburg,et al.  Ptychographic electron microscopy using high-angle dark-field scattering for sub-nanometre resolution imaging , 2012, Nature Communications.

[16]  J R Fienup,et al.  Reconstruction of an object from the modulus of its Fourier transform. , 1978, Optics letters.

[17]  J. Rodenburg,et al.  An annealing algorithm to correct positioning errors in ptychography. , 2012, Ultramicroscopy.

[18]  Nobuo Tanaka,et al.  Direct observation of six-membered rings in the upper and lower walls of a single-wall carbon nanotube by spherical aberration-corrected HRTEM. , 2006, Nano letters.

[19]  Earl J. Kirkland,et al.  Advanced Computing in Electron Microscopy , 1998 .