Lattice resolution of vibrational modes in the electron microscope

The combination of aberration correction and ultra high energy resolution with monochromators has made it possible to record images showing lattice in phonon modes, both a displaced collection aperture more recently an on –axis aperture. In practice the objective include Bragg reflections that correspond observed image spacings, specimen be sufficiently thick for adequate scattered intensity. There been controversy as whether axis detector are really consequence mode or just transfer information from was formed by elastically electrons. We present results calculations based theory includes possibility dynamical electron diffraction incident electrons full dispersion relation. show Umklapp scattering second Brillouin Zone back first is necessary therefore reasonable attribute scattering.