Application of eV neutron scattering and eV neutron absorption techniques

Intense spallation neutron sources can provide a useful eV neutron flux in the energy range 1-100 eV, which is much more intense than has even been available from steady-state sources, and makes two fruitful techniques possible. One is an eV neutron scattering technique. The other is an eV neutron absorption technique. The discovery of superconductivity in the temperature range 30-100 K for the La-Cu-O system and the Y-Ba-Cu-O system is one of the most exciting events in recent solid state physics. Many attempts to explain such extraordinary high Tc values have been made with conventional electron-phonon coupling theory as well as with non-phonon mechanisms. The most direct test for such theories is to look for predicted excitations by using inelastic neutron scattering techniques. The eV neutron scattering and eV neutron absorption experiments can provide new important information for the high Tc mechanism, which has never been obtained by ordinary neutron scattering experiments. For the first time, the author applies these methods to the observation of motions of specific atoms in La-Cu-O and Y-Ba-Cu-O systems. In this paper, he reports a procedure of the application. 17 refs., 8 figs., 1 tab