9:15 AM - 9:30 AM
▲ [10a-Z05-4] Structural and Magnetic Properties of Epitaxial TmFe2O4 Thin Film with Self-assembled Interface
Keywords:hexagonal ferrite, exchange bias effect, spin glass
TmFe2O4, which is a member of the RFe2O4 family (R = Sc, Y, In, and Dy to Lu), manifests both charge and spin orderings and hence, interesting dielectric and magnetic properties are expected. We have grown epitaxial TmFe2O4 thin films on (111)-oriented yttria-stabilized zirconia (YSZ) substrates via a pulsed laser deposition method, and structural and magnetic properties were investigated by the scanning transmission electron microscopy with electron energy loss spectroscopy and magnetic measurements. Interestingly, the hexagonal TmFeO3-δ phase has been found at the interface region between TmFe2O4 thin film and the YSZ substrate with the Tm3+-rich region at the upper side of the substrate. Furthermore, the intrinsic exchange bias effect was observed at 100 K by the spin competition between antiferromagnetic hexagonal TmFeO3-δ and ferrimagnetic TmFe2O4 phases. We also found that TmFe2O4 itself exhibits a spin glass transition due to the strengthened magnetic frustration with oxygen off-stoichiometry.