Magnetization dynamics at elevated temperatures

By using the quantum kinetic approach with the instantaneous local equilibrium approximation, we propose an equation that is capable of addressing magnetization dynamics for a wide range of temperatures. The equation reduces to the Landau–Lifshitz equation at low temperatures and to the paramagnetic Bloch equation at high temperatures. We further include the stochastic fields in the dynamic equation in order to take into account fluctuation at high temperatures. Our proposed equation overcomes the non-analytic damping coefficients in the Landau–Lifshitz–Bloch (known as LLB) equation and can be broadly used for modeling laser pump-probe experiments and heat assisted magnetic recording.

► An effective equation for high temperature magnetization dynamics is derived.
► Importance of longitudinal relaxation at high temperatures is revealed.
► The proposed equation overcomes drawbacks of the previous equation.