We discuss recent advances in the area of plasmon excitations in ion-solid interactions. The basic aspects of plasmons are described, including surface modes. Kinetic plasmon excitation, a major contribution to the energy loss of fast charges in matter, should occur above a threshold ion velocity of similar to1.3 times the Fermi velocity. The unexpected observation of sub-threshold excitation is analyzed with the conclusion that the usually dominant mechanism is indirect excitation by fast secondary electrons. Slow ions with sufficiently high potential energy can excite multipole surface plasmons, as evidenced by the plasmon decay structure in the electron emission spectra. (C) 2001 Published by Elsevier Science B.V.
Plasmon excitation in ion-solid interactions
RICCARDI, Pierfrancesco
2001-01-01
Abstract
We discuss recent advances in the area of plasmon excitations in ion-solid interactions. The basic aspects of plasmons are described, including surface modes. Kinetic plasmon excitation, a major contribution to the energy loss of fast charges in matter, should occur above a threshold ion velocity of similar to1.3 times the Fermi velocity. The unexpected observation of sub-threshold excitation is analyzed with the conclusion that the usually dominant mechanism is indirect excitation by fast secondary electrons. Slow ions with sufficiently high potential energy can excite multipole surface plasmons, as evidenced by the plasmon decay structure in the electron emission spectra. (C) 2001 Published by Elsevier Science B.V.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
