Magnetic planar waveguides as combined polarizers and spin-flippers for neutron microbeams

We propose waveguide structures which transform an incident unpolarized beam into a polarized microbeam and also can be used as spin-flippers by varying the incidence angle on the structure. We describe optimized structures combining these functions. Such waveguides could be used for the investigation of one-dimensional magnetic structures and could be implemented on any existing fixed wavelength reflectometer.

► We propose a waveguide transforming a neutron beam into a polarized microbeam.
► This thin-film device acts as polarizer and spin-flipper for neutron microbeam.
► We calculate optimized parameters of this waveguide.
► Application of waveguides is in investigation of magnetic microstructures.