  Supercontinuum generation is an extensively studied and arguably the most
important and all-encompassing nonlinear phenomenon. Yet, we do not have a good
control over all the signals generated in this process. Usually a large part of
an octave spanning spectrum has orders of magnitude too much weaker signal than
the peak to be useful for any application. In this work we show strong signal
generation within a supercontinuum using a silicon Bragg grating waveguide. We
show up to 23 dB of signal enhancement over a 10 nm full-width-at-half-maximum
bandwidth at the Bragg resonance in the telecom window. Since the grating is
made by depositing charge carriers periodically, thus avoiding any dimensional
change in the waveguide, it can allow other functionalities offered by the
induced electric field, such as second harmonic generation. The ease of grating
fabrication, whether with dimensional variation or doping, makes such a device
useful for enhancing signal strength at any desired frequencies with high
precision within a supercontinuum independent of material platform. We believe
this work opens a new avenue for supercontinuum enhancement on demand in
integrated photonics.
