Larmor labelling by thin spin flippers with rotating magnetic field: simulations of performance of neutron scattering instruments

The neutron spin-echo (NSE) method, that is the most powerful tool of high-resolution neutron spectroscopy, is known in two versions: with the long solenoids and short alternating fields. Here we consider an alternative version that makes use of spin flippers consisting of thin magnetic foils with an in-plane rotating magnetic field vector. MNCP simulations show the perfect performance of the NSE spectrometer build upon such flippers. Requirements to thin magnetic foils are estimated. Some possible applications of such technique are discussed. This approach can be considered as an alternative to the present-day NSE techniques.