Magnetisation and Magneto-Resistance Study of Ferromagnetic Metal/Half Metallic Double Perovskite Bi-Layers

Abstract

We observe a large magneto-resistance in very thin Ba2FeMoO6films of ~-12% at 10K, which is not significantly changed when thin NiFe/Ba2FeMoO6bi-layers are made. This suggests that the magneto-resistance in both cases is dominated by inter-grain tunnelling in the Ba2FeMoO6thin film. There is an anomalous peak in the resistance at ~300K in the bi-layer film that can not be easily explained. However, we know that the temperature where this peak occurs is close to the Ba2FeMoO6Curie temperature.

The effects of oxygen pressure on disordering and magneto-transport properties of Ba2FeMoO6 thin films grown via pulsed laser deposition

“…The positive magneto-resistance (MR) can be linked to spins as the positive MR is observed only in relatively conductive samples; vacuum films at 800 and 900 C (not shown here), not in 700 C vacuum film in previous study. 12 The partial pressure of oxygen is as low as 1 Â 10 À6 Torr for 0.5 mTorr of O 2 /Ar mixture gas and it clearly tells the high sensitivity of the material properties to oxygen. A closer look at the graph in the small field range gives more detailed changes.…”

“…9,10 However, there are a handful of studies on thin film Ba 2 FeMoO 6 by pulsed laser deposition 11 and sputtering. 12 In a previous study, 11 we prepared phase-pure epitaxial thin films under high vacuum and examined the magnetotransport and magnetic properties. In this present report, we have deposited epitaxial Ba 2 FeMoO 6 thin films under oxygen atmosphere and investigated the effect of oxygen on their properties.…”