  This work reports on the measurement of magnetic dichroism in
angular-resolved photoelectron spectroscopy from in-plane magnetized buried
thin films. The high bulk sensitivity of hard X-ray photoelectron spectroscopy
(HAXPES) in combination with circularly polarized radiation enables the
investigation of the magnetic properties of buried layers. Angular
distributions of high kinetic energy (7 to 8 keV) photoelectrons in a range of
about 60 deg were recorded in parallel to the energy distribution. Depending on
purpose, energy and angular resolutions of 150 to 250 meV and 0.17 to 2 deg can
be accomplished simultaneously in such experiments. Experiments were performed
on exchange-biased magnetic layers covered by thin oxide films. More
specifically, the angular distribution of photoelectrons from the ferromagnetic
layer Co2FeAl layer grown on MnIr exchange-biasing layer was investigated where
the magnetic structure is buried beneath a MgO layer. Pronounced magnetic
dichroism is found in the Co and Fe 2p states for all angles of emission. A
slightly increased magnetic dichroism was observed for normal emission in
agreement with theoretical considerations.
