Academic Affiliation: Georg‐August‐University of Göttingen

Talk: October 23, 2018

Bulk impurities studied by Scanning Tunneling Microscopy and Spectroscopy: Introduction to the basic concepts to interpret topographic and spectral features

Scanning Tunneling Microscopy (STM) and Spectroscopy (STS) is the ideal tool to study single atomic scale defects on surfaces. But it is also able utilized to investigate bulk impurities. While this has been shown for semiconductors already shortly after the invention of STM, it came to a certain surprise that also single atom impurity well below a noble metal surface can be visualized and spectroscopically analyzed. To understand the topographic as well as the spectroscopic signatures of such impurities, more advanced solid state concepts like electron-focusing and Kondo-effect has to be used. This mainly educational seminar will provide an introduction in both topics. I will discuss the scattering of electrons in an anisotropic media as well as the signature of a Kondo atom as seen by STS.