The Femtosecond Field Emission Camera: A Device for Continuously Observing the Motion of Single Adsorbed Atoms and Molecules

Abstract

Unlike many laser techniques for achieving fast time resolution, a streak camera generates a continuous record of picosecond phenomena. By applying the beam-sweeping method of the streak camera to the electrons field-emitted from a sharp metal tip, we have developed the femtosecond field emission camera (FFEC), which can continuously record the motion of individual atoms or molecules adsorbed on the tip with a time resolution of 10-13 s. This is fast enough to observe directly the vibrational motion of atoms and molecules. We have recorded the motion of an single Cs atom on a tungsten (111) tip with 1 nm and 2 ps resolution,2 a factor of 106 faster than any previous continuous observation of atomic motion. © 1993 Optical Society of America