Sounds of Atoms

摘要

Early in setting up our nanoscience laboratory at Penn State, we were frustrated because we could not peer into the tunneling junctions of our scanning tunneling microscopes (STMs) to see what the atoms were doing. We were particularly vexed when singular events, such as an atom moving on the end of the STM probe tip, confounded our data and forced us to start over. Such an event was very difficult to identify; it would be just a blip in a recorded image or a flash on an oscilloscope, and it would not be recognizable at all in the frequency spectrum of noise monitored on our spectrum analyzer.