Conception of magnetic memory switched by time dependant current density and current electron spin polarization

Paul Steblinski, Tomasz Blachowicz


In this article the magnetic memory model with nano-meter size made from iron cells was proposed. For a purpose of determining the model specifications, the magnetic probes group with different geometrical parameters were examined using numeric simulations for the two different time duration of transitions among quasi-stable magnetic distributions found in the system, derived from the energy minimums. The geometrical parameters range was found, for which the 16 quasi–stable energetic states exist for the each probe. Having considered these results the 4 bits magnetic cells systems can be designed whose state is changed by spin-polarized current. Time dependent current densities and the current electron spin polarization directions were determined for all cases of transitions among quasi–stable states, for discovered set of 4 bits cells with different geometrical parameters. The 16-states cells, with the least geometrical area, achieved the 300 times bigger writing density in comparison to actual semiconductor solutions with the largest writing densities. The transitions among quasi-stable states of cells were examined for the time durations 105 times shorter than that for up to date solutions.

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