Tunneling Spectroscopy and Inverse Photoemission: Image and Field States

Abstract
Tunneling spectroscopy performed with the scanning tunneling microscope is used to study image-type surface states. The tunneling tip causes a Stark shift and expansion of the hydrogenic image-state spectrum, permitting a clear resolution of the individual states. A simple theoretical model provides a quantitative connection between the tunneling data and both previous and new inverse-photoemission data.