Neutron spectroscopic study of crystal-field excitations and the effect of the crystal field on dipolar magnetism inLiRF4(R=Gd, Ho, Er, Tm, and Yb)

摘要

We present a systematic study of the crystal-field interactions in the LiRF4 (R = Gd, Ho, Er, Tm, and\udYb) family of rare-earth magnets. Using detailed inelastic neutron scattering measurements, we have been\udable to quantify the transition energies and wave functions for each system. This allows us to quantitatively\uddescribe the high-temperature susceptibility measurements for the series of materials and make predictions\udbased on a mean-field approach for the low-temperature thermal and quantum phase transitions. We show that\udcoupling between crystal field and phonon states leads to line-shape broadening in LiTmF4 and level splitting in\udLiYbF4. Furthermore, using high-resolution neutron scattering from LiHoF4, we find anomalous broadening of\udcrystal-field excitations which we attribute to magnetoelastic coupling.