Simulations for imaging with atomic focusers

The basis has been explored for the possible application of the various schemes that have been proposed for making use of the focusing properties of single heavy atoms, or rows of atoms extending through thin crystals in axial directions, for the attainment of ultra-high resolution in electron microscopy. Calculations are reported for the form of 200 keV electron beams channeled along rows of atoms through crystals and propagated in the vacuum beyond the crystals. The conditions for forming beams less than 0.05 nm in diameter have been established. Simulations of images having resolutions of this order are reported for the case that the specimen is placed at the Fourier image position beyond the exit face of a thin crystal and the transmission of the periodic array of ultra-fine beams, translated laterally by tilting the incident beam, may be observable using a conventional transmission-electron-microscopy (TEM) instrument.