Giant Circular Dichroism in Soft X-Ray Photoemission From Non-Magnetic Solids
Olena Fedchenko (Institut für Physik)

We report on the first measurements of circular dichroism in the angular distribution (CDAD) of photoelectrons from non-magnetic samples in the soft X-ray range. The experiment was performed at beamline P04 of PETRA III, providing circularly-polarized photons in a wide energy range from 260-2400eV. The novel technique of ToF k-microscopy is ideal for the study of dichroism. CDAD asymmetry is surprisingly large and reaches almost 80% in some regions. It thus provides a tool of circular polarimeter throughout the soft X-ray range. CDAD shows a pronounced dependence on photon energy and k-vector. It depends on matrix elements and relative phases of partial waves, as shown earlier using conventional electron spectrometers.