Contrast inversion of the apparent barrier height of Pb thin films in scanning tunneling microscopy
Abstract
Scanning tunneling microscopy measurements of the apparent height of the tunneling barrier are analyzed for Pb islands on Ag(111). The apparent barrier height (ABH) significantly varies with the bias voltage. This bias dependence leads to drastic changes and even inversion of contrast in spatial maps of the ABH. Using model calculations, these variations are interpreted in terms of the strongly modulated local density of states of thin Pb films, which is caused by quantum well states.
- Publication:
-
Applied Physics Letters
- Pub Date:
- January 2010
- DOI:
- Bibcode:
- 2010ApPhL..96c3112B
- Keywords:
-
- adsorbed layers;
- electronic density of states;
- lead;
- metallic thin films;
- quantum wells;
- scanning tunnelling microscopy;
- silver;
- work function;
- 73.30.+y;
- 68.43.Mn;
- 68.55.-a;
- 71.20.Gj;
- 68.37.Ef;
- 73.61.At;
- Surface double layers Schottky barriers and work functions;
- Adsorption/desorption kinetics;
- Thin film structure and morphology;
- Other metals and alloys;
- Scanning tunneling microscopy;
- Metal and metallic alloys