A MULTILAYER-COATED DIFFRACTION-GRATING DEVICE FOR POLARIZED AND UNPOLARIZED NEUTRON INTERFEROMETRY

This work is devoted to a new generation of cold-neutron interferomete rs based on bidimensional diffraction. The use of multilayer coatings in the classical Ioffe diffraction-grating neutron interferometer is p roposed. This interferometer combines the properties of two periodic s tructures, namely the dispersion by a diffraction grating and the high reflectivity ensured by the multilayer coating. All the cold-neutron interferometer devices (two diffraction gratings and two mirrors) must be multilayered with Ni-Ti or Fe-Ge for unpolarized or polarized neut ron interferometry experiments, respectively. The computed results, gi ving the characteristics of the multilayer-coated amplitude diffractio n grating are discussed within a kinematic model. An Ni-Ti multilayere d amplitude diffraction grating for use at lambda = 5 angstrom is pres ented as an example.