Gabriel Bertotti

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A novel theoretical approach to magnetization dynamics driven by spin-polarized currents is presented. Complete stability diagrams are obtained for the case where spin torques and external magnetic fields are simultaneously present. Quantitative predictions are made for the critical currents and fields inducing magnetization switching, for the amplitude and(More)
  • I Panea, G Drijkoningen, A J Van Der Veen, G Bertotti, L Matenco
  • 2005
Introduction Receiver arrays are used in seismic acquisition for data reduction. Synthetic modeling a receiver array shows the presence of some end-effects that introduce false " arrivals " on the seismic records. A beamforming technique has been proposed to attenuate their presence from seismic data. Two beamforming methods and their results are presented(More)
  • G Bertotti, M Celasco, F Fiorillo, P Mazzetti, S Shingubara, H Kaneko +13 others
  • 1998
resistance to increase until that area is depleted causing the voids to coalesce which causes the local temperature and current density to drop and consequently the resistance drops. A critical film temperature T c = 254 C was identified at which the maximum height M of resistance transient reaches a peak value M p as a function of current density. In(More)
A single-domain nanomagnet is a basic example of a system where relaxation from high to low energy is probabilistic in nature even when thermal fluctuations are neglected. The reason is the presence of multiple stable states combined with extreme sensitivity to initial conditions. It is demonstrated that for this system the probability of relaxing from high(More)
A general formulation of scalar hysteresis is proposed. This formulation is based on two steps. First, a generating function g(x) is associated with an individual system, and a hysteresis evolution operator is defined by an appropriate envelope construction applied to g(x), inspired by the overdamped dynamics of systems evolving in multistable free-energy(More)
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