ORC Seminar Series

Speaker: Elisabeth Soergel, Institute of Physics, University of Bonn, Germany

Date: Wednesday 18 February 2009
Time: 2pm
Venue: Building 2, Lecture Theatre K

Abstract

In this presentation the capability of scanning force microscopy (SFM) for the investigation of ferroelectric domains will be reviewed. SFM is known to allow measurements with an astonishingly high resolution, topographical structures in the sub-nm regime or forces of less than 10-15 N. To map ferroelectric domains piezoresponse force microscopy (PFM) is used, a technique based on SFM. Interestingly it is not possible to measure the piezoelectric coefficient of a given material or to determine the width of domain walls by means of PFM. However, other important properties of ferroelectric domains such as the depth of surface domains and the real surface charge density are accessibly be PFM. In my talk I will demonstrate the capabilities of SFM not only for a standard ferroelectric (LiNbO3) but also for a multiferroic crystal (HoMnO3).

Biography

After completing a professional education as a classical musician with a diploma degree, Elisabeth Soergel studied physics at the Ludwig-Maximilians University at Munich. There she worked in the group of Prof. Walther at the Max-Planck Institute of Quantum Optics and received her Ph. D. in 1999 on the investigation of photorefractive crystals with scanning force microscopy. Subsequently she stayed as a post-doc at the IBM research laboratories in Rüschlikon (Zurich) in the group of J. Gimzewski working on storage device research with scanning tunnelling microscopy. Since 2001 she is at the University of Bonn working in close relation to the group of Prof. Buse. Here she obtained her habilitation in 2007 on the subject of visualization of ferroelectric domains with piezoresponse force microscopy.  

One of Soergel's research interests is the goal to establish piezoresponse force microscopy as a quantitative and thus an artefact-free method of measurement. Her current interests include ferroelectric domains in ferroelectrics as well as in multiferroics, both under the aspects of their detection as well as their fabrication.