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The angular dependence of magnetoresistance (MR) of the La0.7Ca0.3MnO3 thin film biepitaxial step junction (BSJ) shows a simple sin2(θ) dependence in the in-plane high-field magnetoresistance, with θ being the angle between the applied field and current. This behavior is similar to the spin-orbit coupling-induced anisotropic magnetoresistance (AMR) commonly observed in transition ferromagnetic metals, except for two salient features. First, the maximum MR in the present case occurs at an oblique angle between the applied field (H) and electric current (I), while it is usually observed to occur when H∥I. Second, the AMR in the plane perpendicular to the film surface displays a remarkable value (Δρ/ρ∼8%), which is about an order of magnitude larger than that of the in-plane AMR. Such a large AMR cannot be solely explained by spin-orbit coupling effect. We suggest instead that the metallic and ferromagnetic inhomogeneous granules existing in the BSJ region might have acted as the source of spin-polarized scattering giving rise to the enhanced AMR when the colossal magnetoresistance was measured across the biepitaxial step boundaries. [ABSTRACT FROM AUTHOR]

In the absence of any external applied magnetic field, we have found that a magnetic tunnel junction (MTJ) can produce a significant output direct voltage under microwave radiation at frequencies, which are far from the ferromagnetic resonance condition, and this voltage signal can be increase by at least an order of magnitude by applying a direct current bias. The enhancement of the microwave detection can be explained by the nonlinear resistance/conductance of the MTJs. Our estimation suggests that optimized MTJs should achieve sensitivities for non-resonant broadband microwave detection of about 5000 mV/mW. [ABSTRACT FROM AUTHOR]

The magnetoresistance of a MgO-based magnetic tunnel junction (MTJ) was studied experimentally. The magnetoresistance as a function of current was measured systematically on MTJs for various MgO cross sectional areas and at various temperatures from 7.5 to 290.1 K. The resistance current dependence of the MTJ was also measured for different angles between the two ferromagnetic layers. By considering particle and angular momentum conservation of transport electrons, the current dependence of magnetoresistance can be explained by the changing of spin polarization in the free magnetic layer of the MTJ. The changing of spin polarization is related to the magnetoresistance, its angular dependence and the threshold current where TMR ratio equals zero. A phenomenological model is used which avoid the complicated barrier details and also describes the data. [ABSTRACT FROM AUTHOR]

The effect of gate voltage on hot-carrier induced degradation in drain extended high-voltage metal-oxide-semiconductor (MOS) transistors with thick gate oxide (100 nm) structure is presented. Different from the conventional low-voltage n-type MOS transistors, under a fixed drain voltage, devices stressed at a higher Vgs result in a greater maximum transconductance and on-resistance degradation. Under higher Vgs, the increase in channel hot-carrier injection is responsible for the greater Gm,max degradation. On the other hand, Kirk effect induced increase in drain avalanche hot carriers near the drain as well as higher electric field in the channel is responsible for the greater Ron degradation. [ABSTRACT FROM AUTHOR]