ドイツWuerzburg大のUmbach教授とともに有機薄膜の精密な電子状態測定を行っている
Schoell博士が阪大に来られるのを機会に下記の講演会を開催いたします。
皆様のご参加をお願いいたします。
講師：Dr.Achim Schoell,
University of Wu”rzburg, Experimental Physics II, Germany
“Electronic Structure and Interaction in Organic Hybrid Systems”
日時：平成２０年１１月２７日（木） １３時１５分～
場所：豊中キャンパス 理学部 D307講義室
Abstract:
Organic semiconducting materials and organic-inorganic hybrid systems provide large potential for novel applications in electronic and opto-electronic devices. To realize and optimise these applications a detailed knowledge of the electronic structure as well as of the properties of electrons upon excitation by light or upon charge injection is mandatory. I will demonstrate in this talk how Photoelectron and X-ray absorption spectroscopy (PES and NEXAFS, respectively) can contribute to the understanding of organic semiconductors and their contacts to metals. Next to the determination of the occupied and unoccupied energy levels, which are relevant for charge transport, the interaction between the molecules in epitaxically grown thin films will be of particular interest. By high-resolution NEXAFS spectroscopy the ???-interaction between hetero-aromatic molecules can be identified and localised. The interaction leads to a delocalization of the respective orbitals, which are also involved in the charge transport. At the interfaces to metal contacts strong — in some cases covalent — interaction can occur, which leads to the generation of interface states. These states can be crucial for the charge injection and may as well hinder or promote the transport of charge between molecule and metal. On the example of model molecules on single crystalline metal surfaces I will show, how a combination of spectroscopic techniques allows identifying metal-organic interface states and provides information on the energetics, the spatial distribution, and the dynamics of electrons at interfaces.
