Epitaxial thin films of hexagonal ErMnO3 fabricated on Pt(111)/Al2O3(0001) and
yttria-stabilized zirconia(111) substrates exhibited both ferroelectric character and
magnetic ordering at low temperatures. As the temperature was reduced, the
ErMnO3 films first showed antiferromagnetism. At lower temperatures, the films
deposited at lower oxygen partial pressures exhibited spin glass behaviour. This reentrant
spin glass behaviour was attributed to competition between an
antiferromagnetic interaction in the hexagonal geometry and a ferromagnetic
interaction caused by a change in Mn valence induced by excess electrons from the
oxygen vacancies.
Oxygen Vacancy Induced Re-Entrant Spin Glass Behaviour in Multiferroic
ErMnO3 Thin Films. S.Y.Jang, D.Lee, J.H.Lee, T.W.Noh, Y.Jo, M.H.Jung,
J.S.Chung: Applied Physics Letters, 2008, 93[16], 162507