# Is the polarisation field stimulated emission?

I'm told that polarisation happens due to the oscillation of an electric dipole and stimulated emission is due to the excitation of an electron between energy levels but both depend on the incoming light frequeny. Are they the same or if not what's the difference?

In a liear medium the relationship between electric field and polarization vector is $$P=\epsilon_0\chi E$$. This electric field $$E$$ might carry a frequency if it is a time-dependant field, and thus we can see the relationship between polarization and electromagnetic field. This field however may be the result from stimulated emission, i.e the field itself is the stimulated emission, and the polarization is a part of this, but they are not the same. They are connected to each other however. Of course stimulated emission is related to the strength of the incoming field, but the polarization vector is also dependent due to this relation.