Determination of Orbital Location of Electron-Induced Secondary Electrons by Electric Field Visualization

The electric field around positively charged biological specimens is studied by electron holography. By the amplitude reconstruction process for holograms, the orbits of electron-induced secondary electrons are clarified on the nanometer scale. It is found that the stationary orbit of secondary electrons can be directly located without disturbing their motions under the condition that the current of secondary electrons in stationary orbit is considerably larger than that of incident electrons. The experimental conditions for the induction of the stationary orbit of secondary electrons are discussed, and furthermore the theoretical basis of the orbital location of secondary electrons through electric field visualization is discussed in the framework of quantum mechanics.