Question on the implementation of temperature-dependent magnetic parameters in Mumax3
Enlong Liu
Dear Mumax3 Community,
Recently, I planned to implement temperature-dependent magnetic parameters, like Ms, Ku and Aex into Mumax3 code. I checked previous work and found that there seems to be different methods to do so. But I still have some questions on this topic.
The basic inclusion of temperature in mumax3 is ‘Temp = 300K’, for example. In my case, however, I need temp to change during simulations, following a function of simulation time t Temp = T(t). So the first method is just to change the above code to ‘Temp = T(t)’. My first question is that if by changing the Temp code only, Ms, Ku, and Aex change correspondingly. I tried to print the above parameters to the output txt, they didn’t change with respect to simulation time (or temperature). But I was told by someone that this should work.
The next method I tried is to add analytical equations of Ms etc. to let the code calculate those parameters for each step. The psudo-code is like below:
Temp = T(t)
Msat = Ms(T(t))
Ku1 = Ku(T(t))
Aex = Aex(T(t)).
The complete code is attached to this email. In this way, What I suppose is that both the stochastic thermal field and the magnetic parameters are changing with simulation time (with temperature). And the output file indeed recorded the change of magnetic parameters.
The above case is actually based on a PhD thesis, where the author used similar code, but disabled Temp definition, only used the psudo-code below:
Msat = Ms(T(t))
Ku1 = Ku(T(t))
Aex = Aex(T(t)).
What I can understand is that in this way, magnetic parameters change with simulation time, but the thermal fluctuation field does not.
I wonder if any of you could clarify the 3 cases above. I really appreciate your time and help!
Best regards,