Neutron Brillouin Scattering Experiments with Pulsed Neutrons on High Resolution Chopper Spectrometer HRC

摘要

We improved the High Resolution Chopper Spectrometer (HRC), which is installed at MLF in J-PARC, in order to perform neutron Brillouin scattering (NBS) experiments, and successfully demonstrated a feasibility of this method. Gapless spin-wave excitations were observed in La_(0:8)Sr_(0:2)MnO_3, which were in good agreement with previous results using single crystals, on the other hand, a large energy gap in the ferromagnetic spin waves was found in SrRuO_3. Spin-wave peaks in a permanent magnet Nd_2Fe_(14)B were on the dispersion curve determined previously using a single crystal. Excitations, so-called fast sound, in liquid D_2O were in a good agreement with previous inelastic neutron scattering experiments and the dispersion curve were extended to the lower Q region.