C++ main module for emicrom Package  1.0
Cross Tie Example

The cross tie examples consists in studing a thin sheet of permalloy.

The sheet is rectangular with 0.64 micron of width, 1.28 micron of height & 0.01 micron of length.

The mesh constains 64 cells in X direction, 128 cells in Y direction & 1 cell in Z-direction.

mesh

Ms Aimantations (A/m) 1.7e6
K Anisotropy (J/m^3) 1.0e5
A Exchange (J/m^3) 1.e-11
L reference length (m) 1.e-8
L/Le exchange influence 4.26

The anisotropy direction U1 is uniformly in the Y-direction with uniaxial crystal type The initial magnetism M is oriented in the Y direction in half of the domain and in its opposite in the secund part.

initial magnetism value along y main anisotropy direction

The simulation parameters are:

relaxation taylor expansion
time optimal
relaxation rate 1.e-8
toeplitz vector product LC
L/Le exchange influence 4.26

The the results are as follow:

The value of magnetism field at equilibrium state are plot as follow:

equilibrium magnetism value along x equilibrium magnetism value along y equilibrium magnetism value along z

equilibrium magnetism vector with total magnetism module equilibrium total magnetic excitation field norm

In order to vizualize the effect of the diffusion process we have to change the matter data to respect the relation $ L~0.4 Le $: The matter parameters are as follow:

Ms Aimantations (A/m) 1.7e6
K Anisotropy (J/m^3) 1.0e5
A Exchange (J/m^3) 1.e-9
L reference length (m) 1.e-8
L/Le exchange influence 1

The configurations is as follow:

The value of magnetism field at equilibrium state are plot as follow:

equilibrium magnetism vector with total magnetism module< equilibrium total magnetism field norm
equilibrium magnetism vector along X at iter 723 equilibrium magnetism vector along Y at iter 723 equilibrium magnetism vector along Z at iter 723
Hysteresis cycles are also computed with Hext varying form [0,-0.5,0] to [0,0.5,0] from increment of 0.001 for A=1.e-9 with several implementations of toeplitz . vector product: <
3 hysteresis cycles for elementary circular product 3 hysteresis cycles for elementary tensor product3 hysteresis cycles for RP implementation of elementary tensor product

PS: to show the field of M apply the filters to field M: