  Since Purcell's seminal report 75 years ago, electromagnetic resonators have
been used to control light-matter interactions to make brighter radiation
sources and unleash unprecedented control over quantum states of light and
matter. Indeed, optical resonators such as microcavities and plasmonic
nanostructures offer excellent control but only over a limited spectral range.
Strategies to tune both emission and the resonator are often required, which
preclude the possibility of enhancing multiple transitions simultaneously. In
this letter, we report a more than 590-fold radiative emission enhancement
across the telecommunications emission band of Erbium-ions in silica using a
single non-resonant plasmonic waveguide. Our plasmonic waveguide uses a novel
reverse nanofocusing approach to efficiently collect emission, making these
devices brighter than all non-plasmonic control samples considered. Remarkably,
the high broadband Purcell factor allows us to resolve the Stark-split electric
dipole transitions, which are typically only observed under cryogenic
conditions. Simultaneous Purcell enhancement of multiple quantum states is of
interest for photonic quantum networks as well as on-chip data communications.
