Franz J. Giessibl (University of Regensburg, Germany ) — October 6, 2016
Atomic force microscopy (AFM) and scanning tunneling microscopy (STM) image surfaces with atomic resolution enable local spectroscopies such as of current versus voltage and forces versus distance. In the past, STM and AFM used to be separate techniques that required their own instrumentation. While STM had better spatial resolution than AFM, the situation is now reversed with modern AFM . Angular dependencies of chemical bonding forces have been observed before for Si tips interacting with Si surfaces , W tips interacting with graphite  and similarities exist between metal tips interacting with CO molecules on Cu and Si atoms . In the latter two cases, light atoms such as carbon or oxygen interacted with much heavier and much larger metal atoms. Gross et al. established that CO is an excellent probe for organic molecules. For example, pentacene can be imaged at excellent resolution with CO terminated tips . Tips made of permanent magnets such as CoSm allow to resolve the spin order in the antiferromagnetic insulator nickel oxide . Complex surface terminations of the topological insulator TlBiSe2 have been determined by AFM . The stiff cantilever/small amplitude technique used here also allows true atomic resolution in ambient conditions , and small iron clusters on Cu (111) are resolved by force microscopy . Very recently, AFM has provided important insights into inelastic tunneling spectroscopy  and superconductivity .
In this seminar, we will review many exciting avenues in nanoscience research that are opening up today when combining both STM and AFM techniques.
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Franz Giessibl is University Professor at the University of Regensburg. He received a diploma in experimental physics in 1988 with Prof. Gerhard Abstreiter in Munich and continued with a PhD in physics with Nobel Laureate Gerd Binnig at the IBM Physics Group Munich on atomic force microscopy. He continued experimental and theoretical work on the force microscope at the chair of Prof. Jochen Mannhart at University of Augsburg where he received a habilitation in 2001. In 2006, he joined the faculty at the Department of Physics at the University of Regensburg in Germany.
Giessibl spent most of his professional career improving atomic force microscopy. His work has enabled atomic force microscopy to obtain subatomic spatial resolution on individual atoms and submolecular resolution on organic molecules.