Scanning Tunneling Spectroscopy of Magnetic Bulk Impurities

Magnetic impurities in a non-magnetic host metal have been actively explored in condensed matter physics in recent last decades. From both fundamental and applied viewpoints these systems are very interesting because they can exhibit strong electronic correlations that give rise to various fascinating phenomena beyond the single particle picture. Up to now our understanding of the underlying processes remains limited due to difficulties involved in measuring these systems on a microscopic scale. With their unique control, scanning tunneling microscopy (STM) and spectroscopy (STS) allow for the first time investigations of phenomena occurring on very small length and energy scales. Here, single magnetic iron and cobalt atoms embedded beneath a metal surface are investigated using these techniques. In particular, the transition from single impurity Kondo physics to two interacting impurities is studied in real space. This thesis contains a comprehensive description of the STM /STS technique, sub-surface impurities, as well as single- and two-impurity Kondo physics - and as such offers a valuable introduction to newcomers to the field.

Winner of the Jan Peter Toennies prize awarded by the University of Göttingen A short literature summary at the beginning of each chapter introduces the reader to state-of-the-art experimental and theoretical work Provides a general introduction to single-impurity and two-impurity Kondo physics in real space Includes supplementary material: sn.pub/extras

Inhalt
Introduction.- Experimental Setup and Background.- Investigation of Sub-surface Atoms by STM.- Kondo Physics of Single Sub-surface Atoms.- Signatures of Non-magnetic Atoms.- Two-Impurity Kondo Physics.- Prospects.- Appendix.