Scanning Tunneling Microsopy Basics Transmission coefficient critically dependent on the distance btw. tip & surf. Electron energy level densities Electron.

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Presentation transcript:

Scanning Tunneling Microsopy Basics Transmission coefficient critically dependent on the distance btw. tip & surf. Electron energy level densities Electron flow A bias voltage needs to be applied:

 V bias is necessary to raise the Fermi level and create free levels for the electrons. Tunneling probability depends on the existence (and density) of free levels.  V bias is positive or negative with reference to the tip’s Fermi level.

Basics of tunneling

Atomic Force Microsopy -