Neutron inelastic scattering study of rare-earth orthoferrite HoFeO3

•Spin dynamics of the Fe subsystem does not change through SR transitions.•NN interactions in Fe sublattice along c-axis and ab-plane has different energies.•Exchange integrals for interaction Fe-Ho and Ho-Ho have opposite signs. By the single crystal inelastic neutron scattering the orthoferrite HoFeO3 was studied. We show that the spin dynamics of the Fe subsystem does not change through the spin-reorientation transitions. The observed spectrum of magnetic excitations was analyzed in the frames of linear spin-wave theory. Within this approach the antiferromagnetic exchange interactions of nearest neighbors and next nearest neighbors were obtained for Fe subsystem. Parameters of Dzyaloshinskii-Moriya interactions at Fe subsystem were refined. The temperature dependence of the gap in Fe spin-wave spectrum indicates the temperature evolution of the anisotropy parameters. The estimations for the values of Fe-Ho and Ho-Ho exchange interaction were made as well.