  The light scattering properties of superconducting (Tc=3.8 K) heavily boron
doped nanocrystalline diamond has been investigated by Raman spectroscopy using
visible excitations. Fano type interference of the zone-center phonon line and
the electronic continuum was identified. Lineshape analysis reveals Fano
lineshapes with a significant asymmetry (q=-2). An anomalous wavelength
dependence and small value of the Raman scattering amplitude is observed in
agreement with previous studies.
