In a system consisting of two different charged species we identify the excitation of a second, low-frequency plasmon. At strong coupling the doublet of high-frequency (first) and low-frequency (second) plasmons replaces the single-plasmon excitation that prevails at weak coupling. We observe the formation of the second plasmon from the acoustic Goldstone-type mode associated with a short-range interaction as the range is extended to infinity.
ASJC Scopus subject areas
- Physics and Astronomy(all)