ABSTRACT
Applications of the thermal neutron spectroscopy to the study of lattice and magnetic dynamics in rare-earth borides is discussed. A brief presentation of the main specifics of the neutron spectroscopy method is given. The results of the phonon excitation study as well as 4f-electron excitation spectra, based on the data obtained with single-crystal and polycrystalline samples, are discussed in detail. The attention is focused on the hexa- and dodecaborides which demonstrate a wide range of the physical phenomena related to strong electron correlations. The features of the intermediate-valence state of samarium in SmB6 are discussed in connection with the lattice dynamics and magnetic excitation spectra. The latter are analyzed over a wide energy scale, from intermultiplet transitions to the resonant mode in the spin gap and quasielastic excitations. Then, we present and discuss the main results of the neutron spectroscopy study on the typical Kondo insulator YbB12 . Special attention is focused on the resonant mode (spin exciton) and the spin-gap transformation due to the temperature and impurity effects.
