/*****************************************************************  

  Description: 
   This mumax3 script computes the hysteresis curve of a 2D system
   with a complex geometry.

   This file is written for the mumax3 workshop organised for the 
   spintronic seminar series in the summer of 2020. For more 
   information go to https://www.mumax.ugent.be/mumax3-workshop
  
  Authors:

   Dr. Jonathan Leliaert (jonathan.leliaert@ugent.be)
   Dr. Jeroen Mulkers    (jeroen.mulkers@ugent.be)

******************************************************************/

//square thin-film mesh with 1600 nm side length
SetMesh(512, 512, 1, 3.125e-09, 3.125e-09, 20e-09, 0, 0, 0)

//permalloy like material parameters
Msat = 800e3
Aex = 1e-11
alpha = 0.01

//add drawing of real sample
real:= imageShape("drawing.png").scale(1, 0.5, 1.).transl(0, -400e-9, 0)

//define 6 perfect circles
perfect := circle(350e-9).repeat(600e-9, 400e-9, 0).transl(0, 200e-9, 0).intersect(yrange(0, inf))

//set the geometry
setgeom(perfect.add(real))

//define 2 regions, default region =0
defregion(1, yrange(0,inf))
defregion(2, circle(400e-9).transl(550e-9, -600e-9, 0))

//set material parameters in regions
Ku1.setregion(1,2e4)
anisu.setregion(1,vector(1,0.1,0))

Aex.setregion(2,2e-11)
msat.setregion(2,400e3)

//set initial magnetization in regions or shapes
//default = randommag
m.setinshape(real, uniform(1, 0, 0))
m.setregion(2, vortex(1, 1).transl(550e-9, -600e-9, 0))

//relax the magnetization in saturated state
B_ext=vector(0.1,0,0)
tableadd(B_ext)
relax()

H_min  := -0.1
H_max  :=  0.1
H_step :=  0.002

//ramp the field down
for H:=H_max;H>=H_min;H-=H_step{
    B_ext=vector(H,0,0)
    minimize()
    tablesave()
    snapshot(m)
}

//ramp the field up again
for H:=H_min;H<=H_max;H+=H_step{
    B_ext=vector(H,0,0)
    minimize()
    tablesave()
    snapshot(m)
}