  We study the effects of the phonon-phonon coupling on the low-energy electric
dipole response within a microscopic model based on an effective Skyrme
interaction. The finite rank separable approach for the quasiparticle random
phase approximation is used. Choosing as an example the isotopic chain of
Calcium, we show the ability of the method to describe the low-energy $E1$
strength distribution. With one and the same set of parameters we describe
available experimental data for $^{48}$Ca and predict the electric dipole
strength function for $^{50}$Ca.
