# MIF 2.1 # a simple system of to illustrate the effect of temperature scaling in dependence of the cell size # starting conditions are Mx = Ms, My = Mz = 0 # The temperature leads to a decrease of the magnetization # make sure that the time step is small enough! # for details see: #Temperature in micromagnetism: cell size and scaling effects of the stochastic Landau–Lifshitz equation # https://doi.org/10.1088/2399-6528/ab31e6 # Marc Benjamin Hahn 2019 J. Phys. Commun. 3 075009 Destination archive1 mmArchive Schedule DataTable archive1 Step 1 Destination archive2 mmArchive Schedule Oxs_TimeDriver::Magnetization archive2 Stage 1 Parameter temperatur 1800 Parameter damp 0.5 Parameter cells 1e-9 Parameter ani -5.7E3 Parameter dtime 10e-15 Specify Oxs_BoxAtlas:nickel " xrange {0 [expr {30*$cells}]} yrange {0 [expr {30*$cells}]} zrange {0 [expr {10*$cells}]} " Specify Oxs_RectangularMesh:mesh " cellsize {$cells $cells $cells} atlas :nickel " #specify exchange energies Specify Oxs_Exchange6Ngbr { default_A 9e-12 atlas nickel A { nickel nickel 9e-12 } } Specify Oxs_Demag {} Specify Oxs_CubicAnisotropy " K1 { Oxs_AtlasScalarField { atlas :nickel default_value -5.7E3 values { nickel $ani } }} axis1 {1 0 0} axis2 {0 1 0} " # Specify atemperature and timestep you want to use Specify UHH_ThetaEvolve " do_precess 1 alpha $damp fixed_timestep $dtime temperature $temperatur uniform_seed 111 " # specifiy evolver UHH_thetaevolve Specify Oxs_TimeDriver [subst { basename ./NiThin_d"$damp"_c"$cells"_a"$ani"_dt"$dtime"_t"$temperatur" vector_field_output_format {binary 4} scalar_output_format %.15g evolver UHH_ThetaEvolve mesh :mesh stopping_time 5e-11 stage_count 0 Ms { Oxs_UniformScalarField {value 490e3} } m0 { Oxs_UniformVectorField { norm 1 vector {1 0 0} } } } ]