Synchrotron research in general and in particular – scientific possibilities at BESSY II and new developments in photoemission spectroscopy
Dr. Antje Vollmer
Beamtime Coordination BESSY II Helmholtz Zentrum Berlin für Materialien und Energie GmbH
17:00 - 18:00 Tuesday 14 October 2014 KFU HS 5.01 From Terahertz to hard X-rays, from Femtoseconds to hours form paleontology to novel materials – research opportunities at BESSY II. This presentation will give an overview over the manifold science fields and scientific infrastructure at the storage ring BESSY II in Berlin. Selected examples will shed light on the diversity of research, developments, and possibilities a large scale facility can offer.
In a second part of the talk emphasis is given to a new development in photoemission, the novel Angle Resolved Time Of Flight electron energy analyser (ARTOF) which facilitates the simultaneous recording of kinetic energy and angular pattern of photoelectrons with very high energy resolution (100µeV). Its transmission (250 times higher than in hemispherical analyzers allowing for very mild conditions during the experiment) turns the ARTOF into the predestined instrument to investigate sensitive specimens such as organic single crystals, as extremely low photon fluxes can be used. Investigating the electronic band structure under gentle conditions is a necessary prerequisite to unravel the electronic structure in radiation sensitive samples. Here I will present the full energy dispersion of rubrene and tetracene single crystals obtained with unprecedented quality within only a few hours of measurement time using the ARTOF instrument.
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