You don't need complicated setups with superconductors. To a surprisingly good approximation the conduction electrons in a metal behave as a nearly ideal gas. This is the [free electron gas model][1], or unexcitingly named [nearly free electron gas model][2].

This electron gas supports oscillations that are the equivalent of sound waves, and with these comes a quasiparticle analogous to the phonon called the [plasmon][3].

When I was doing my PhD there was lots of interest in plasmons. I'm not sure how active an area it is these days - I get the impression that the more esoteric aspects of electronic structure have largely taken over - but a quick Google will find lots of related material.

  [1]: https://en.wikipedia.org/wiki/Free_electron_model
  [2]: https://en.wikipedia.org/wiki/Nearly_free_electron_model
  [3]: https://en.wikipedia.org/wiki/Plasmon