A recent study [PRB 100, 075427 (2019)], finally, demonstrated plasmon-analog
of refractive index enhancement in metal nanostructures, which has already been
studied in atomic clouds for several decades. Here, we simply utilize this
phenomenon for achieving continuously-tunable enhanced Cherenkov radiation in
metal nanostructures. Beyond enabling Cherenkov radiation from slow-moving
particles, or increasing its intensity, the phenomenon can be used in
continuous-tuning the velocity cutoff of particles contributing to the
Cherenkov radiation. More influentially, this allows a continuously-tunable
analysis of the contributing particles as if the data is collected from many
different detectors, which enables data correction. The phenomenon can also be
integrated into lattice metal nanostructures, for continuous medium tuning,
where a high density of photonic states is present and the threshold for the
Cherenkov radiation can even be lifted. Additionally, vanishing absorption can
heal radiation angle distortion effects caused by the metallic absorption.Comment: 10 pages, 7 figure
