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Thermal field


\begin{displaymath}
\mathbf{H}_\mathrm{th}=
\eta
\sqrt{
2 \frac{\alpha}{1+\a...
...frac{k_B T}{\mu_0 \gamma' \Delta x^3 M_\mathrm{s} \Delta t}
}
\end{displaymath}

$\eta$ 1 standard Gaussian process with mean zero and variance 1
$\alpha$   damping constant,
$k_B$ (J/K) Boltzmann's constant,
$T$ (K) Temperature,
$\gamma'$ (1/Ts) gyromagnetic ratio ([*]),
$\Delta x^3$ (m$^3$) discretization volume
$\Delta t$ (s) step size of time integration

Then, the equation of motion ([*]) is integrated for each computational cell for a certain discrete time step. Since the magnetization distribution has changed, the effective field is calculated again, before the next time integration step is performed.



Werner Scholz 2000-05-16