TOWARD DIRECT OBSERVATION OF THE ATOMIC-STRUCTURE OF BIOMOLECULES WITH NANOMETER SPATIAL-RESOLUTION BY VISIBLE-LIGHT

We describe a single-atom source of electrons of a new type based on r esonant tunneling of electrons from Si needles through a thin epitaxia l him of CaF2 coating via the levels of dopant Sm ions in this coating . The results of the first experiments on the implementation of such a source are presented. We consider the possibility to apply such a sin gle-atom source of electrons as an active element for an electron-fluo rescence spectromicroscope that would simultaneously possess subnanome ter spatial resolution and chemical selectivity.