Abstract
Neon, argon, and xenon bubbles in aluminum have been investigated by means of electron-energy-loss spectroscopy. The spectra of the aluminum films containing neon or argon bubbles show the existence of bubble surface plasmons, whereas those containing xenon bubbles do not exhibit a bubble surface plasmon. A treatment by the effective-medium theory was successful in explaining positions and intensities of the bubble surface plasmons or their disappearance.