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fangohr / paper-supplement-standard-problem-dmi

Electronic and additional information for manuscript on micromagnetic standard problem DMI
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doubt about procedure to obtain the spin wave #3

Open Falconcp opened 4 years ago

Falconcp commented 4 years ago

Dear,

I have a question about the procedure to obtain graph 5 of the article, you said that: "We save these components in a matrix, where every column is a magnetization component, mx, my or mz, of the spins across the spatial x-direction, and every row represents a saved time step saved in the previous step "

I think that the table should be:

     mx (r0) ... mx (rf), my (r0) ... my (rf), mz (r0) ... mz (rf) t1 t2 t3 t4 . . .

where r0 and rf represent the start and end points along the strip, then I perform the fft.

I am right? or is the average magnetization saved,

Thanks

davidcortesortuno commented 4 years ago

Hi, you have to save only a single component for the matrix, either mx my or mz; so if you have n spins:

           x0     x1   x2   ...
t0        mx(0) mx(1) mx(2) ... mx(n)
t1        mx(0) mx(1) mx(2) ... mx(n)
...

then you do a 2D Fourier transform (and apply a signal window, check the Python library) which gives you k-space for the spatial coordinates and w (frequency) space for the time

Falconcp commented 4 years ago

thanks so much

Falconcp commented 4 years ago

Once the matrix is obtained, the procedure to obtain the figure 5 is taking the fft2 of the matrix mentioned above. I think that the first column of the matrix would be the wave vectors and the other components the frequencies?