Subpicosecond atomic motion detection and signal transmission.

摘要

A time-dependent record depicting the motion of one or more selected atoms with a time resolution equal to or shorter than 10<-><1><2> second is generated by applying an electric field to a field emission tip (10). Electrons emitted from the selected atoms are focused into a beam which is swept over a spatially resolved electron detector (14) for sensing the intensity of the beam as a function of the for creating the record. One- or two-dimensional records can be generated without signal averaging. The electrons can be directed onto a spot on a surface where dynamics are to be probed, and the electrons scattered or emitted from said surface are then focused into the electron beam. This method can also be used for transmitting information to a remote location at high frequency.