The effect of biquadratic coupling on spin transfer torque-assisted magnetization switching in the pentalayer nanopillar device is studied by numerically solving the magnetization switching dynamics of the free layer governed by the Landau- Lifshitz-Gilbert-Slonczewski (LLGS) equation. The spin transfer torques can, for example, be described by a Landau-Lifshitz-Gilbert (LLG) equation or variants of Landau-Lifshitz Bloch equations , which include both reactive and dissipative components representing the Magnus and drag forces mentioned above, respectively. The phase diagram of the magnetization precession is calculated and categorized into four states according to their characteristics. 9,10 STT and SOT magnetic random access Spin-transfer torque (STT) oscillator with synthetic antiferromagnet (SAF) acting as a free magnetic layer is studied. A theory of magnetization dynamics in ferrimagnetic materials with antiparallel aligned spin sublattices under the action of spin-transfer torques (STTs) is developed. exchange term in the Landau-Lifshitz-Gilbert equation allows capturing some aspects of spin dynamics beyond the macro-spin approximation. Temperature gradients are treated \`a la Luttinger by introducing a fictitious gravitational field that couples to the energy density. In this equivalence, the intensity of spin-transfer e ect on the nanopillar gcorre-sponds to the angular velocity by the dissipation parame-ter, 0. Theoretical treatments usually begin by treating the magnetization within the ferromagnetic film as asinglemacrospin.6 Spin-torque effects are then taken into account phenomenologically by modifying the macrospin’s dynamical Landau-Lifshitz-Gilbert (LLG) equation.1 The setup yields an equation of motion equation, which is equivalent to the dynamics of a nanopil-lar under the e ect of a spin-transfer torque generated by a uniform electric current, eq. Features related to the spin currents, the spin‐transfer torque and their dependence on both magnetic and electric external fields are then calculated and discussed. (2). I will try to illustrate its physical meaning by using a general example. Skyrmions can be driven by spin-orbit torques as a result of the spin Hall effect. of the Landau-Lifshitz-Gilbert equation that contains two additional terms, the adiabatic and nonadiabatic spin-transfer torques. The equation that describes spin dynamics is called the LLG equation, named after Landau, Lifshitz and Gilbert. The novelty of the model lies in the fact that the voltage dependence of TMR has been modeled using a single equation dividing it into three different operating regions. Spin-transfer-torque, a transfer of angular momentum between the electron spin and the local magnetic moments, is a promising and key mechanism to control ferromagnetic materials in modern spintronic devices. N2 - We propose a generalized stochastic Landau-Lifshitz equation and its corresponding Fokker-Planck equation for the magnetization dynamics in the presence of spin-transfer torques. I. Lifshitz equation (1) and the spin-diffusion equation (3) self-consistently. magnetization, and is the ratio of the nonadiabatic spin transfer torque to the adiabatic one [24,25]. This effect de-scribes the transfer of angular momentum from electrons spin polarized by a fixed magnet and delivered in the form of a torque to flip the magnetization of a free magnetic layer. We also allow for an external magnetic field along this axis. Spin-transfer torques, both reactive and dissipative, induced by temperature gradients in conducting ferromagnets are calculated microscopically for smooth magnetization textures. Since the spin-transfer torque can pump a magnetic energy into the magnetic system, the equilibrium temperature of the magnetic system is ill defined. Both macrospins experience a uniaxial anisotropy ω A in the direction . • Bloch-Bloembergen-Slonczewski equation is adopted to study short-wavelength magnon excitation. • High frequency up to the terahertz (THz) scale is … spin transfer torque does not need an external field but takes a relatively long time for the switch due to an incubation time. 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