OBSERVATION OF NEUTRON GUIDED-WAVES FROM THE OPEN-END OF A THIN-FILM WAVE-GUIDE AND A WAVE-GUIDE INTERFEROMETRY

Neutrons guided wave propagation were observed at the open end of a th in film waveguide. A low-index-leaky waveguide coupler is used for cou pling the incident beam into the thin guiding film. After guided propa gation over a distance of a few millimeters, the neutrons are diffract ed at the open end of the guide giving a Fraunhofer diffraction patter n. The diffracted neutron intensity distribution is in fairly good agr eement with thp theory. An interferometer based on the splitting of th e far-field pattern on two separate peaks is proposed. (C) 1998 Americ an Institute of Physics. [S0021-8979(98)06802-9].