Neutron diffraction study of hexagonal manganite YMnO3, HoMnO3, and ErMnO3 epitaxial films

The antiferromagnetic phase transition in epitaxial RMnO3 (R = Y,Ho,Er) films of thickness 450-500 nm was investigated by neutron diffraction by recording the intensity variation of magnetic reflections as a function of temperature. For YMnO3 and ErMnO3, the Neel temperature for the Mn3+ ions ordering is of 66 and 68 K, respectively. For HoMnO3, the magnetic 011 reflection, which normally appears in bulk, is very weak and thus the onset of the Mn3+ ordering is not clearly observed; at 50 K there is a magnetic phase transition, which temperature corresponds to the reorientation temperature in bulk HoMnO3. (C) 2008 American Institute of Physics.