Temperature-dependent ferromagnetic resonance via the Landau-Lifshitz-Bloch equation : Application to FePt
نویسندگان
چکیده
Using the Landau-Lifshitz-Bloch (LLB) equation for ferromagnetic materials, we derive analytic expressions for temperature-dependent absorption spectra as probed by ferromagnetic resonance. By analyzing the resulting expressions, we can predict the variation of the resonance frequency and damping with temperature and coupling to the thermal bath. We base our calculations on the technologically relevant L10 FePt, parametrized from atomistic spin dynamics simulations, with the Hamiltonian mapped from ab initio parameters. By constructing a multimacrospin model based on the LLB equation and exploiting GPU acceleration, we extend the study to investigate the effects on the damping and resonance frequency in μm-sized structures.
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