In this paper we present an extended transport model that has been specifically derived to account for the silicon thickness dependence of low-field electron mobility as observed in ultra-thin silicon-on-insulator MOS transistors, operating both in single-and double-gate modes. The systematic comparison with available experimental data suggests that conventional models for bulk transistors are inadequate to quantitatively describe the peculiarities of electron transport in such devices. The role of bulk phonons, surface roughness and Coulomb scattering is analysed, together with that of surface optical phonons and of the space, low-frequency fluctuations of the silicon thickness of such devices. Simulation results show that the inclusion of the last two scattering mechanisms significantly improves the comparison with available experimental data.

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We have studied the high field susceptibility of nickel-platinum alloys in fields up to 150 kOe, at temperatures between 4.2 and 300 K. The high field susceptibility is analysed in the ferromagnetic and paramagnetic range by means of Arrott plots and Landau coefficients. The paramagnetic initial susceptibility follows a Curie-Weiss law, with a Curie constant independent of nickel concentration. The results are compared with those obtained for palladium-nickel alloys. We discuss the experimental data in the framework of recent theories on itinerant ferromagnetism.

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In the framework of first-order theory, differential cross sections for e--H scattering in the presence of a laser field have been calculated. In the calculation, the dressed wavefunction of Byron and Joachain was used. The effect of exchange was taken into account explicitly. Both the dressing and the exchange effects are sensitive to the direction of the laser field. In a sufficiently intense laser field, the effect of exchange is virtually absent, i.e. the incident electron seems to be distinguishable from the target electron.