An inelastic neutron scattering investigation of holmium orthoferrite.

The inelastic neutron scattering spectra recorded in this study and elsewhere provide a useful set of crystal-field (CF) energy levels for the ground= 6 term of Hoin HoFeO. The resolution of the low-energy, temperature-dependent pseudo-quadrupole ground state splitting and magnon peaks is consistent with the self-ordering of the Hosublattice at∼ 8-10 K and supports earlier electron spin resonance investigations of the Homagnon behaviour. Systematic analysis of the grouped singlet CF levels of Ho: HoFeO, in conjunction with the CF Kramers doublet levels of the neighbouring Er: ErFeO, has yielded possible sets of CF parameters for the two systems.