Dresden 2017 – wissenschaftliches Programm
O 59.31: Poster
Dienstag, 21. März 2017, 18:30–20:30, P2-OG1
A time of flight delay line detector for characterization of electron emission from metal nanostructures — •Andreas Wöste, Jan Vogelsang, Thomas Quenzel, Petra Groß, and Christoph Lienau — Institut für Physik, Carl von Ossietzky Universität, 26129 Oldenburg, Germany
Strong-field photoemission from metallic nanostructures has recently been of considerable interest since e.g. electrons can be accelerated in large near field gradients or above threshold ionization may be induced from long-lived image potential states. A microscopic understanding of those processes requires detector systems capable to collect information about the emitted electron momentum distribution. One way to investigate this is via a hemispherical deflection analyzer. The recorded kinetic energy and the emission angle then enables extracting information about the local optical nearfields at the surface. However these kind of detectors lack the capability to measure the complete momentum distribution of the photoemitted electrons. To overcome those restrictions we implement a time of flight delay line detector (TOF-DLD) enabling simultaneous measurement of emission angles as well as the perpendicular and parallel momentum of each photoelectron individually. We test this by investigating the strong field electron emission from a sharply etched gold nanotip. With the TOF-DLD we are able to study the dependency of emission angle on the kinetic energy. To verify proper working of the new detector system we compare selected measurements with the results of a known hemispherical deflection analyzer.