Experimental test of the rotating magnetic field neutron spin-echo technique: Spin-echo and MIEZE for large energy transfers

Here we are describing the experimental realization of the rotating magnetic field neutron spin echo (RFSE) technique that is based on spin turners using truly rotating magnetic fields. RFSE has no practical limit for short Fourier times and a "shorty'' instrument mode built on this principle can be easily used at generic neutron spin echo spectrometers to increase their dynamical range beyond that provided by currently used methods. The upper limit for Fourier times is estimated. The tripling of the field integral (and hence the maximum Fourier time) by means of the bootstrap method is experimentally demonstrated. The suitability of RFSE for the use of Fresnel-type correction elements aiming to equalize the field integral for divergent neutron beams scattered by the sample is shown. The experimental realization of the MIEZE method using the RFSE technique allowing for studies of depolarizing samples and/or with depolarizing sample environments is presented.