CONTROL SPIN CURRENT AND DATA RECORDING ON SPIN STORAGE MEDIUM

Abstract

The paper presents the results of experimental studies of the physical mechanisms and dynamics of magnetization reversal of the films Al 2 O 3/ Tb 25 Co 5 Fe 70/ Al 2 O 3, Al 2 O 3/ Tb 22 Co 5 Fe 73/ Al 2 O 3, Al 2 O 3/ Tb 19 Co 5 Fe 76/ Al 2 O 3, Al 2 O 3/ Co 30 Fe 70/ Al 2 O 3 with a single magnetic layer and the films Al 2 O 3/ Tb 22 Co 5 Fe 73/ Pr 6 O 11/ Tb 19 Co 5 Fe 76/ Al 2 O 3, Al 2 O 3/ Co 80 Fe 20/ Pr 6 O 11/ Co 30 Fe 70/ Al 2 O 3 with two magnetic layers radiated by picosecond (τi ≈ 80 ps ) and femtosecond (τi ≈ 130 fs ) laser pulses. The experimental samples of spin transistors and data recording devices on the spin storage medium are also described. The results of studies have shown that magnetic switching effects in the nanolayers under femtosecond laser pulses can be used for creation of systems of high-speed controlling of spin currents with the response time τ ≤ 10-11s. Conclusions from the studies are the following: thermomagnetic switching under the influence of an external magnetic field or a demagnetization field, magnetic switching of antiferromagnetic films under the influence of an effective internal field of antiferromagnetic interaction between magnetic sublattices rare-earth and transitive metals, magnetic switching under the influence of a magnetic field of the inverse Faraday effect, or under the influence of a magnetic field of a spin current. The magnetic switching of magnetic layers under action of the magnetic field of a spin current is the most important for practical use in elements of spintronics. This mechanism of magnetic reversal takes place only in multilayer nanofilms and the heterogeneous multilayer magnetic nanofilms are the base material for creation of spintronic devices. The great advantage of the magnetization reversal of magnetic nanolayers of the spin current is that the mechanism of magnetization reversal is working in the films with perpendicular anisotropy and in the films with in-plane anisotropy. The injection of polarized electrons can also be realized using short electrical pulses. That is why the mechanism of magnetization reversal of the control electrodes spin current is the most appropriate for the management of high-spin current in the elements of spintronics. On the basis of this mechanism, we have realized the high-speed recording of information on the spin carrier and the experimental model memory with three magnetic nanolayers. The data recording in this memory cell is realized using an electric nanosecond pulse.