A neutron spin interferometer using two RF-π/2 flippers

We have developed a neutron spin interferometer using radio frequency (RF) spin flippers. A polarized neutron is split or superposed in the spin space with an RF-π/2 flipper. This interferometer provides three types of interference patterns with high visibility (≳0.9) and high phase resolution (<0.3%) in spite of its simple structure. The principle and structure of the spin interferometer are described and results of performance tests are presented and discussed. The non-homogeneity of an output beam which is expressed as a superposition of two energy eigenstates are demonstrated.