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A surprising inverse (positive) MR effect was observed in thin film of magnetite (Fe 3 O 4 ) grown on Si substrate by pulsed laser deposition (PLD). Transmission electron microscopy (TEM) and X-ray diffraction (XRD) measurements show a highly (111)-textured growth and single phase nature of Fe 3 O 4 thin film. X-Ray Magnetic Circular Dichroism (XMCD) and X-ray absorption spectroscopy (XAS) were employed to exclude the existence of γ-Fe 2 O 3 . The surface morphology of the film was investigated by atomic force microscopy (AFM). Based on the aforementioned studies, we proposed a spin dependent conduction mechanism to explain the observed anomalous MR effect.

We report a pulsed laser deposition (PLD) growth of VMn/CoCrPt bilayer with a magnetic coercivity ( H c ) of 2.2 kOe and a grain size of 12 nm. The effects of VMn underlayer on magnetic properties of CoCrPt layer were studied. The coercivity, H c , and squareness, S , of VMn/CoCrPt bilayer, is dependent on the thickness of VMn. The grain size of the CoCrPt film can also be modified by laser parameters. High laser fluence used for CoCrPt deposition produces a smaller grain size. Enhanced H c and reduced grain size in VMn/CoCrPt is explained by more pronounced surface phase segregation during deposition at high laser fluence.

A method for pinning synthetic antiferromagnet (SAF) based spin-valves is presented, which allows pinning to be established perpendicular to the setting field H. As the SAF (AP1/Ru/AP2) magnetizes, its layer moments undergo a spin-flop transition for a magnetic field H = HSF, and align with H for H = HSat. The magnetization of layer AP1 is perpendicular to H for a field H = HGold. This field corresponds to the maximum GMR on HSF

D.c. electric field induced second-harmonic generation (SHG) spectroscopy of the Si(001)–SiO2 interface was studied both experimentally and theoretically. To describe the experimental results the general phenomenological model of d.c. induced SHG in centrosymmetric semiconductors is developed, taking into account surface and bulk field dependent as well as field independent contributions to the non-linear polarization. The solution of an inverse problem within this model of d.c. induced SHG allows all surface and bulk contributions to the non-linear response from an Si(001)–SiO2 interface to be distinguished.