FM||NM module models the interface between a ferromagnet and a non-magnet, capturing the spin-torque on the magnet at the interface.
The FM|NM module is modeled with a series and shunt conductances as shown below:
Where the shunt is on the "NM" side and the spin current flowing through it is the spin-torque, which can be provided to an LLG module.
Parameter | Symbol | Units |
Conductance | ||
Polarization | - | |
Slonczewski like torque coeff. | - | |
FIeld like torque coeff. | - |
The matrices above are for magnet in +z direction. To obtain conductances matrices for a magnet is any general direction "m",we need to basis transformation these matrix, the transformation matrix being obtained by Rodrigues formula. The rotation matrix is given as:
where, and are equatorial and azimuthal angles referenced from the direction. This information is provided to the module using the third terminal "m".
The matrices can then be rotated using the transformation formula:
The module, as a part of the library, can be downloaded here.