Magnon mode transition in real space

Spin excitation of an ilmenite FeTiO(3) powder sample is measured by time-of-flight inelastic neutron scattering. The dynamic magnetic pair-density function D(M)(r, E) is obtained from the dynamic magnetic structure factor S(M)(Q, E) by the Fourier transformation. The real space spin dynamics exhibit magnon mode transitions in the spin–spin correlation with increasing energy from no-phase-shift to π-phase-shift. The mode transition is well reproduced by a simulation using the reciprocal space magnon dispersions. This analysis provides a novel opportunity to study the local spin dynamics of various magnetic systems.