# geoana.em.fdem.MagneticDipoleLayeredHalfSpace.skin_depth#

property MagneticDipoleLayeredHalfSpace.skin_depth#

Returns the skin depth for an electromagnetic wave in a homogeneous isotropic medium.

The skin depth is the propagation distance at which an EM planewave has decayed by a factor of $$1/e$$. For a homogeneous medium with non-dispersive electrical conductivity $$\sigma$$, magnetic permeability $$\mu$$ and dielectric permittivity $$\varepsilon$$, the skin depth for a wave at frequency $$f$$ is given by:

$\delta = \frac{1}{\omega} \Bigg (\frac{\mu \varepsilon}{2} \bigg [ \bigg ( 1 + \frac{\sigma^2}{\omega^2 \varepsilon^2} \bigg )^{1/2} - 1 \bigg ] \Bigg )^{1/2}$

where $$\omega$$ is the angular frequency:

$\omega = 2 \pi f$

For the quasistatic approximation, dielectric permittivity is ignore and the skin depth simplifies to:

$\delta = \sqrt{\frac{2}{\omega \sigma \mu}}$
Returns
float

Skin depth for the EM planewave. Returns the quasistatic approximation if the property quasistatic of the class instance is True.