Voigt–Thomson law

Voigt–Thomson law describes anisotropic magnetoresistance effect in a thin film strip as a relationship between the electric resistivity and the direction of electric current:


 * $$\rho (\vartheta) = \rho_0 + \Delta \rho \cdot cos^2 \vartheta$$

where:
 * $$\vartheta \ $$ is the angle of direction of current in relation to the direction of magnetic field
 * $$\rho_0 \ $$ is the initial resistivity
 * $$\Delta \rho \ $$ is the change of resistivity (proportional to MR ratio)

The equation can also be expressed as:


 * $$\rho (\vartheta) = \rho_\parallel \cdot cos^2 \vartheta + \rho_\perp \cdot sin^2 \vartheta$$

where:
 * $$\rho_\parallel \ $$ is the parallel component of resistivity
 * $$\rho_\perp\ $$ is the perpendicular component