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Understanding and improving the contact resistance of two-dimensional materials for the fabrication of next-generation devices is of vital importance to be able to fully utilize the new physics available in these materials. In this work, eight different contact metals (Ag, Au, Cr, Cu, In, Mo, Ni, and Ti) have been investigated using the same sample of monolayer MoS2. Through the fabrication and testing of multiple, identically sized field-effect transistor devices per contact metal, we compensate for large variability in electrical properties of as-grown chemical vapor deposition MoS2 and deduce the relative performance of each metal. The general trend of lower work function metals having lower contact resistance holds with In, Ag, and Ti performing the best of the metals tested. Our results are compatible with recent research suggesting that the contact resistance in undoped, monolayer MoS2 is dominated by a lateral junction resistance, and we provide context for how this manifests in device-to-device variation. Multiple orders of magnitude differences in contact resistance are observed between metals and can be explained by this lateral barrier operating in the thermionic-field emission regime. [ABSTRACT FROM AUTHOR]

Magnetization switching provoked by spin injection is studied in Ni nanowires of various sizes and morphologies. The response of the magnetization to current injection is measured as a function of the amplitude of the current, the temperature, and the symmetry of the interfaces. The efficiency of the response of the magnetization of spin injection is a decreasing function of the temperature, does not depend on the current sign, and occurs only in the case of asymmetric interfaces. It is shown that the switching provoked by spin injection is not affected by the presence of a magnetic domain inside the layer. Some consequences in terms of spin transfer or exchange torque are discussed. [ABSTRACT FROM AUTHOR]