Magnetization switching in bistable nanomagnets by picosecond pulses of surface acoustic waves

Abstract

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High-frequency magnetoacoustic resonance through strain-spin coupling in perpendicular magnetic multilayers

“…When strain (strain amplitude of 0.5%) is applied, the system shows a large-angle magnetization precession and switching occurs in 3 ns. We also note that Vlasov et al ( 46 ) have recently predicted switching in an elliptical nanomagnet with shape anisotropy.…”

Spin-lattice dynamics model with angular momentum transfer for canonical and microcanonical ensembles

“…As we have demonstrated that the model works well in the absence of an phenomenological Gilbert damping, which consists mainly of electronic contributions, the SLD model can be employed to study magnetic insulators, such as YIG, where the principal contribution to damping is via magnon-phonon interactions. Future application of this model includes controlling the magnetisation via THz phonons 7 which can lead to non-dissipative switching of the magnetisation 11,12 . With the increased volume of data stored, field-free, heat-free switching of magnetic bits could represent the future of energy efficient recording media applications.…”

“…The excitation of THz phonons leads to a magnetic response with the same frequency in Gd 7 , proving the necessity of considering the dynamics of both lattice and spins. Phonon excitations can modulate both anisotropy and exchange which can successfully manipulate [8][9][10] or potentially switch the magnetisation 11,12 , ultimately leading to the development of low-dissipative memories.…”

Anatomy of inertial magnons in ferromagnets

“…Due to the symmetry of N , equation (7), and hence all its roots, remains independent on the direction of H and the equilibrium magnetization m 0 with respect to the wave propagation direction along the z -axis. For each positive wavenumber k , the determinant ( 7) is solved for ω.…”

“…After the first description of the dynamics of the magnetization by Landau and Lifshitz [1], Gilbert proposed an equation that contains a correction due to the precessional damping [2,3]. Since then, the so-called Landau-Lifshitz-Gilbert (LLG) equation is known to give an excellent description of the dynamics of the magnetization, including ferromagnetic resonance (FMR) and magnetostatic waves [4,5], as well as the magnetization reversal [6,7]. Ferromagnetic resonance and time-resolved magnetization measurements allow its spatially homogeneous precession (k = 0) but also non-uniform modes of the magnetization precession (k = 0, where k is the wave vector of spin waves) to be measured [8][9][10].…”