Polarizing Fe-Co-Fe Planar Waveguides for the Production of Neutron Microbeams

Planar waveguides can transform a conventional neutron beam into a very narrow but slightly divergent microbeam. Such microbeams could be used for the investigation of nanostructures with a high spatial resolution. We have investigated the tri-layer magnetic structure Fe/Co/Fe which transforms an unpolarized incident beam into a polarized microbeam. The polarized neutron reflectometer NREX with a horizontal sample plane was used for the waveguide characterization. Some practical aspects of microbeam extraction and polarization are discussed.