Magnetic structure and phase transition at the surface region of Fe3O4(100)

Abstract

Abstract The magnetic structure and phase transition of the near-surface region of Fe3O4(100) was investigated by 57Fe conversion electron Mössbauer spectroscopy (CEMS) and theoretical calculations. It is revealed that at 300 K the magnetization is in-plane in the surface region and cants from the in-plane to the 〈111〉 direction in a deeper region suggesting the presence of a noncollinear magnetic structure. The critical exponents for the tetrahedral and octahedral sites are estimated to be 0.24 ± 0.01 and 0.28 ± 0.01, respectively. Near the critical temperature, furthermore, the magnetization direction in the surface region was found to deviate from the in-plane direction.