Imaging Phonon Excitation with Atomic Resolution
H. Gawronski,*
M. Mehlhorn,
K. Morgenstern
Inelastic electron tunneling spectroscopy at low temperatures
was used to investigate vibrations of Au(111) and Cu(111). The
low-energy peaks at 9 millielectron volts (meV) on Au(111) and
21 meV on Cu(111) are attributed to phonons at surfaces. On
Au(111), the phonon energy is not influenced by the different
stacking of the surface atoms, but it is considerably influenced
by different atomic distances within the surface layer. The
spatial variation of the phonon excitation is measured in inelastic
electron tunneling maps on Au(111), which display atomic resolution.
This atomic resolution is explained in terms of site-specific
phonon excitation probabilities.
* To whom correspondence should be addressed. E-mail: gawronski{at}fkp.uni-hannover.de
