In BornAgain, for the time being, a sample is always represented by an
instance of class
MultiLayer, even if it is a single-layer SAS sample.
The sample is created by the constructor call
sample = ba.MultiLayer()
Layers are then added using either of
sample.addLayer(layer) sample.addLayerWithTopRoughness(layer, roughness)
The layer added first is the top layer (typically vacuum). The layer added last is the bottom layer (typically substrate).
Global properties of the sample are set through the following functions:
which takes an argument of type RoughnessModel;
where the argument is the vertical roughness correlation length in nm;
where the argument is the external magnetic field in A/m.