More recently, electron diffraction was demonstrated with single- and double-slits using
focused ion beam (FIB) milled nano-slits [7, 8]. In addition, one single slit in a double-slit
was closed by FIB induced deposition [9]. This process is not reversible, so observation of the
electron probability distribution through both single-slits could not be done. Also, using a fastreadout
pixel detector, electrons were recorded one at a time and stacked into a final diffraction
pattern [10], but intermediate spatial patterns were not reported.