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– X V – ICPTTFN Magnetization Reversal of Synthetic Antiferromagnets Using Magnetic Field Pulse Perpendicular to Reference Plane Dzhezherya Yu.1, Iurchuk V. 2, Demishev K.2, Korenivski V. 3 1 2 Institute of Magnetism, National Academy of Sciences of Ukraine, Kiev, Ukraine National Technical University of Ukraine “Kiev polytechnic institute”, Kiev, Ukraine 3 Royal Institute of Technology, Stockholm, Sweden The properties of novel systems – so-called synthetic antiferromagnets (SAF) which are the basic elements for magnetoresistive random-access memory (MRAM) cells – are widely studied now. SAF consists of two dipolecoupled elliptical magnetic layers with a small aspect ratio separated by thin non-magnetic spacer. Previous works devoted to the investigation of spin dynamics revealed collective acoustical and optical spin resonant modes in such systems. High-frequency investigations of the two coupled macrospins in SAF cell showed that system’s behavior is similar to Kapitsa pendulum. In-plane AC magnetic field was proposed to use for the cell’s state operation. Here we study the magnetization dynamics of SAF for the case when the external magnetic field is perpendicular to cell’s basic plane. Switching conditions between SAF’s equilibrium states have been considered. It has been shown that at definite conditions a high-speed switching without any relaxation processes can take place. A major problem in controlling the magnetization process in SAF is to organize a switching between two ground states with opposite values of antiferromagnetism vector to avoid long-lasting relaxation processes. Analysis of SAF dynamics equations in different external perpendicular magnetic field configurations allows deriving an optimal profile for the excitation field as (*) H ( t ) = − H ch ( t ) , z 0 where H 0 is the field amplitude and is the pulse duration parameter. No relaxation oscillations near the new equilibrium state should be observed for such field profile. The amplitude of the external field can be reduced by adjusting of the duration parameter, which is extremely important for MRAM operation. It should be noted that remagnetization can be done using the field pulses with the shape close to (*) (e. g. Gaussian or Lorentzian) but in this case we cannot totally avoid the damping oscillations during transition to the new SAF state. The possibility to operate SAF cell using by means of perpendicular magnetic field pulses has been demonstrated. It has been shown that remagnetization of the system can be realized in non-inertial mode using field signals of a specific shape. 375