Ralph R. Ruf, R.J. Gambino
Review of Scientific Instruments
Conductivity, magnetization, and Mössbauer spectra have been measured for a thin film of composition Fe0.503+Fe0.192+Ga1.37O3, sputtered from a target of FeGaO3. The film shows thermally activated electrical conductivity in the range 150-300 K with activation energy 0.26 (2) eV, and a room temperature resistivity of 3×104 Ω-cm. Signs of electronic relaxation typical of inhomogeneous mixed-valence materials appear in the Mössbauer spectra, but the activation energy there is smaller. The oxide orders ferromagnetically around 155(10) K. At 4.2 K, hysteresis is observed with a coercivity of 4.7 kOe, and a reduced remanence of 0.46. The ferromagnetism of the amorphous oxide is attributed to ferromagnetic interactions associated with Fe2+↔Fe3+ electron transfer, which are stronger than the usual Fe3+-O-Fe3+ antiferromagnetic superexchange.
Ralph R. Ruf, R.J. Gambino
Review of Scientific Instruments
S. Von Molnar, C.N. Ruy, et al.
Journal of Magnetism and Magnetic Materials
J.M.D. Coey
Journal of Applied Physics
R.J. Gambino, T.R. McGuire, et al.
IEEE Transactions on Magnetics